Okay, so I've been playing this for a few weeks now. Some observations.
Weird learning curve. Lucky there's a good wiki about the game.
There was a long stretch of nearly no progression a little way in. You max out your first frame fairly quickly, and then you need Neural sensors to build anything else. The only place to get those is the boss of the fifth planet, or you can buy them 12 plat apiece, which is absurd. Once past that hump, though, most mats can be gotten with a little effort. Only thing I can't seem to get are Argon Crystals, to get me a Kubrow pet. :(
I still really enjoy the mission variety, though a couple are pretty similar. I finally got everything to build the Archwing. Simultaneously cool and hard to control, and seemingly completely disconnected from eventing else in the game. Awesome that they put that in there, though!
Apparently, they don't do plat discounts on consoles for login rewards, and I started playing the week after the summer sale. Still, I'll probably drop $20 on it soon, so I don't have to delete character slots. I've got a steady stream of new frames already lined up. My original frame (Mag) is still pretty great- I just potatoed her, and holy hell she kicks ass. My second frame (Valkyr) is kind of underwhelming. That's fine, though, Ember will finish building tomorrow, and Rhino just needs me to press go. I have most of the pieces of Oberon, and the Vauban print, but none of the components, which is a bummer, because he sounds interesting.
All in all, I'm finding it pretty fun, at least until The Taken King shows up. Though, apparently v17 (with the new movement, etc.) was submitted to cert on the Xbone today, and they say it'll take a couple weeks to work thorough that... which puts it in direct competition with the Destiny expansion. Which will hold my interest?