Wondering what the pit falls could be 
I’ve set up a default project, installed my favourite assets.
Got it set up to perfection, then backed up “Assets” folder to windows.
When creating a new project, I then slap in the new back-up Assets folder into the project, hit re-import and takes 20/30 seconds to clean it’s self up and bam!
back to a working environment…
I’ve done some little projects whilst doing this method and not bumped into an issue yet.
my question is:
Is this ok to do?
The Unity police aren’t going to come around and stop you if that’s what you’re asking.
You’ll probably run into problems when you try to drop this assets folder into a project created using a later version of Unity, where there were changes to the file structures of files in the Assets folder between the two versions. You’re likely much better off just exporting everything in your Assets folder as a custom package, then importing that package into any later projects. That way any translation of the files would occur as needed and in the manner Unity QA actually would be running regression tests on.