Lack of documentation/workflow/content examples for mobile 3d shoot'em up/spaceships shooter

hi everybody!
i don’t know if this is the right place for this post,i’m developing essentially using blueprint right now so i have posted it here.

not my first project in unreal engine 4 but i have never had so many problems,doubts and no aswers as i started with this 3d spaceships shoot’em up/shooter for mobile.
i have the impression that some crucial aspects for this kind of genre are incompleted or not developed at all or not documented at all ,
this might explain the very few numbers of games of this genre using unreal engine,but i might have missed some…

All the examples offers informations only on certain aspects of a game of this genre,usually 2d examples,or just 3d movement or performance demanding projectiles firing
but even books or people tutorials don’t provide all the info needed to work on a project like this,especially on mobile where you have to optimize at maximum the perfomance.
or at least that’s what i found,i hope i’m wrong ,for this reason i made the post.
in a game like this you have to see the projectiles,but line trace is cheaper and generally the way to go…so?even in the twin stick shooter twich,the guy explains that they had to remove enemy projectile shooting beacuse it was too much for the hardware they had as showcase…if even they cannot do it…instant hit isn’t the solution,projectiles neither…
navmesh can’t be used with flying ai,ok go for waypoints,but what if we need to keep all the randomness and pathfinding and complex beahviour we can obtain easily for any other “walking” ai using a simply navmesh plane?i found a plugin but i’m pretty sure it’s too much for a mobile shoot’em up…any cheaper way to fake it?navmesh volume in progress for next releases of the engine?epic suggested workflows?
i have the feelings that these aspects aren’t taken much in consideration,event that this kind of genre of game isn’t so much important for the developer of the engine…there’s plenty of stuff for any other thing
it’s not even a question of using blueprints or c++ here i think…

something that i’ve missed?documentation ,examples or whatever i didn’t consider/notice/found?do i have to consider other game engines,i’d rather not to…,more suitable for this kind of games?

if possible also to have some answer from epic staff that would be great…
thank you guys!