I plan on making an ambitious game in the future that’ll have CGI cutscenes. Is it best to make this in something like Blender and import it into Unity? Or do it manually in Unity? Which is the most performant?
To create models of characters you cannot do that in Unity (you have to use Blender or similar). To animate them (e.g. make them walk and talk) I think is where the real question is. Blender has tools for this, as does Unity. So both are possible - but do you want to create the animation yourself or use animation clips someone else has created? Then are you going to just record a video of the cutscene and play the video? Or are you going to animate it in the game? For example, if you want to let the player define the character and change their clothes, animating the character in the game makes more sense - so your character is dressed correctly.
I don’t think there is a single correct solution. If you just create a video file, then you have a lot more freedom it how to create it. The cutscene is just playing a video file, nothing more special needed. It also means you can use video editing tools to polish up the result (e.g. adjust colors, add special effects, text overlays, whatever).
Yeah the ideal is a video file, a prerendered cutscene. I’m just worried as to the amount of space that will take up in the game file - but I figure that wouldn’t be an issue nowadays, since a lot of modern phones have 64 GB + storage space.