I played this for the first month after release and then dropped it. Is it worth coming back to now?
Depends why you dropped it.
There was a lot of new content since release. The most recent and biggest one is the third faction from the first game : Illuminist.
Automatons and Terminids receive new enemy type and objectives.
New stratagems (mecha, a car, different support weapons, backpack...), weapons etc....
Also this summer there was a big balancing patch that kind of buff every weapons and stratagems. I was scare for the balancing of the game but it worked quite well.
You can run everything and have fun.
Narrative wise the Illuminists are pulling a black hole toward Super Earth that destroy every planets on its way. It destroyed its first planet yesterday.
Basically the core gameplay stays the same that at launch but with more variety in the equipment you can take. And there is much less crashes/bugs.
If you like the gameplay loop, it's definitely worth coming back ! Community and devs are still very active.