Not sure if this is the right section to ask this, but I was wondering which of these game ideas you think would be best. I am kind of stuck in deciding, I won’t go into depth into each game, as it is just a broad outlook as of now, I would just like others opinion on which is best.
P.S. - They are pretty random.
Thanks
How many games you made?
Trucking Simulator. 
I’m the first vote. 
I’ll be honest, I haven’t officially release any major games but have worked on many, and I would like to start a new one from scratch.
You actually think so? Most people ive asked said a trucking sim would just be too boring, you need more action.
6 can be very cool. Yes the formulaic approach has been done again and again and … much like the “big” movies.
Just throwing these out for your consideration:
I like the medieval time period. But all of these games (RPGs) being made to “look” like they are medieval… most of them are not medieval. Not really. They could have swapped out graphics and just as easily have a sci-fi game with aliens patrolling the world.
I would have never expected to see Trucking Sim up there in the list.
Well it starts off as a Trucking sim in the not too distant future. Lol!
He! He! Lol!
And you’re a gun for hire contract worker.
Or an undercover detective from the future policeman/bountyhunter like Captain Falcon.
Who is undercover and investigating lots of suspicious activity in the Trucking world.
But at the same time, making money on the side, from trucking. Lol!
PS: the Captain falcon type idea is waaaaaaaaaaaaaay better. lol!
And you have rival truckers competing with you too.
Some of them could be bad guy’s. Lol!
You drive your Truck to one of many job points.
The bosses of each place, tells you and other truckers to load up the respective cargo onto your trucks.
And as soon as you load the cargo, the boss tells you all, whoever "drops the cargo off in one piece, to the destination point and reaches 1st, gets a small contract or a ton of money.
You race your trucks at super sonic speed, (a mix of sim and arcady style driving mechanics,) to the destination point on your maps.
If you reach 1st, you get a ton of money/prizes to buy parts or upgrades for your truck.
(You can even put Lazers etc. on your trucks too.) Lol!
Some stages can have random elements, such as futuristic punk gangs, or crazy Aliens etc, trying to steal the cargo from your futuristic sim truck as you race rival truckers.
Talk about drama! Lol!
Oh and in some stages, you have to be careful, not to accidently drop/lose, too much of the cargo.
Otherwise if you do, and you come first, you may get money, but not any “secret prizes.”
Oh,…and some of the Truck cargo bosses are badguys too.
Now what do you think about that?
It may be more than just your average truck Sim, but more super Cool!! 
LOL!
I’ll be brutally honest here:
None of these are good ideas, because they’re not ideas at all; they’re themes. You’re really asking which thematic genre appeals most to us, not which of the games we think would be more fun.
That said, a theme is a useful place to start - it can inform a lot of your design decisions. But you must be able to tell the difference between a theme and a gameplay idea, otherwise you will get stuck in a bottomless pit of trying to make a game out of a concept without considering what your end goal might be.
So I’ll be nice now and review your thoughts.
OK, maybe not that nice.
1. World War ll Simulator (But more of an Arcade feeling)
Simulator, eh? It’s odd you should choose that word. Typically a World War II game is a shooter, but the AAA industry has been there, done that, and you’ll never be able to match their efforts, even considering the post-CoD4 popularity decline of that genre. But what else might you be able to do with that theme? What really is a “Simulator” with “more of an Arcade feeling”?
2. Survial Game - A Pandemic Outbreak (Across the entire world)
If, when you say “Pandemic Outbreak”, the idea of zombies has not even crossed your mind, this is an interesting idea. Would you be immune to the disease, and civilization has now collapsed, thus leaving you and maybe a handful of survivors to stay alive? Or would you have to avoid being infected? If you did get infected, what would you do besides waiting to die? I could imagine some intense moments where you have to find a cure for yourself. But if a cure exists, why is everyone else dead…?
3. Trucking Simulator - (Would just be NA)
zzzzzzzzzzzzzz… oh sorry dozed off there for a minute.
In all seriousness, if you have a passion for trucking, this might just do the trick. But I know that I don’t, and I would probably stab my eyes out with a spork before finishing a game like that.
4. Modern World War
Hmmm, a modern World War would be an interesting geopolitical situation, wouldn’t it? Most modern wars right now are either between smaller nations, or larger nations vs terrorist groups. A true World War III would be many larger nations pitted against each other, like the first two - except now most of these larger nations have nuclear weaponry. So what kind of game do you make out of this? Certainly not just another Call of Duty clone - that would be a waste of the idea of such a massive war. Unfortunately, I don’t have any better ideas.
5. Open World Game - Like GTA, but with new ideas
… So, you’re gonna make a game that’s like one of the most expensive games ever to leave production, on your own, and add “new ideas” in your spare time?
If you keep the scale realistic, though, open world games can be a lot of fun. I have no idea what kind of development effort is involved for a simple one, but I’d imagine most of the effort goes into filling the city with lots of interesting things to do. If you keep it pretty simple and rely on emergent content and behaviors to fill out the experience, I think the scale would be quite realistic for an indie, although it’s probably still too big for an inexperienced one-man team.
6. Medieval Game (Has been done alot, would take a new look on things)
Medieval fantasy? Or actual medieval? What does this do for gameplay? Medieval fantasy tends to focus on small parties of heroes slaying monsters, while a historical medieval game typically focuses on larger-scale battles between nations. The latter means lots of AI - or worse, lots of networking. So a fantasy game is probably the way to go. As for what you do with that… I have no clue. The medieval fantasy genre is everything from World of Warcraft to Dwarf Fortress.
Thanks for the detail response! Some of the ideas that I had for each theme,
1. World War ll Simulator (But more of an Arcade feeling)
A game that actually feels like your on the front line of WW2. World at War was a great game and had the dark atmosphere that a WW2 game should have, but the issue here is I feel I cannot remake World At War. It was a huge game and took years, and it one of the most successful WW2 games ever made. I just thought a good WW2 game hasent really been released since 2008, with the exception of CoH.
2. Survival Game - A Pandemic Outbreak (Across the entire world)
This is personally my favourite, but I feel that it would get boring within time to play. I was aiming for survival in a sense like Dayz, but more realistic. The world is normal, until a new pandemic (like SARS, very deadly) spreads and billions die, and you are fighting for survival. You would have to fight both the virus plus other players and NPCs, because the world would go crazy if something like this did happen. People would panic, and would hoard resources and whatnot. There would be hotspots for the virus, stronger spots than others. It would take a few days to die after getting infected, giving you time to find a cure.
3. Trucking Simulator - (Would just be NA)
Oddly enough, this is winning right now. Would be interesting to remake a map of NA with somewhat accuracy of detail. I do agree not everyone is into rigs, but those that are into them, love them. This might just create a superior player base.
4. Modern World War
This one is pretty open, it has never been tested, the technology in today’s military would make it tough to see what would realistically happen.
5. Open World Game - Like GTA, but with new ideas
Your right, this was a shot in the dark. A lot of people enough Open World though, so on a smaller scale of GTA, its out there.
6. Medieval Game (Has been done alot, would take a new look on things)
I would make it less fantasy, as there are many games like that. Skyrim, but without magic. The problem here is without magic people may find just swords and arrows boring to play.
Any other thoughts?
Lemme add a game to the vague list:
Some type of casual game (match 3, word game, calculation). It’s a good first project, because you’re doing minimal work on the graphical/animation side, but it would teach you the logic side (programming against Unity’s branch of .NET). Then move on to something actiony (shooter, platformer). Finish a few simple projects in order, then move on to massive projects 
All of these have been done a lot and none of them were interesting.
If you’re going to make something basic due to a lack of ability or time-capacity, you should probably make it unique and simple.