I decided to start a new save and forgo the new expedition feature in the Anomaly. I feel like part of the fun is starting from scratch and finding shortcuts to get units, complete milestones, etc. Plus I often play my expedition saves even after the expedition is over.
I made it to Phase 3 before I quit playing today. Overall I like the expedition. Nothing has been particularly annoying but I guess that could change in the next phases.
How's it going for everyone else?
I finished today as well. Overall, I thought it was fine. It's clear it was meant to show new players different parts of the game. I was actually glad it was so succinct without much grinding. Almost everything you need was within the confines of the expedition, either as a reward or available somewhere along the path.
While I always like the cosmetic rewards, it annoys me that the colors and textures never quite match the existing customizations. I wish they would go back and make everything a little more consistent.
I often keep playing my expedition saves and get them into an end-game state. I haven't decided if I will this time.
Your point about grinding is a good one. I think it was the last expedition (?) that had milestones like "discover a hot-blooded animal" which required just jumping around and and randomly searching, and eventually I just looked up a spoiler because I couldn't be bothered with that grind.
Certainly I made things a little easier for myself by loading up on various resources from my main save, but doing it from scratch would've been pretty painless.