> missing some of the favorite Mass Effect things (like the Geth)

Some of that is interestingly handled in the Andromeda novels and there were hints that even some of the cancelled DLC was going to reintroduce some of those elements, but EA diverted the DLC teams to Anthem instead.

I think a large part of the issue is that the sum total of ME trilogy is a hard act to follow, without aiming to sound hyperbolic it's a very bright light that outshines a lot. Anything trying to be a sequel has a difficult balancing act of being familiar versus being different and bringing new ideas in.