Title is self-explanatory, and directed moreso at the monetization front rather than the gameplay since the gameplay’s really solid and fun.
FOMO:
Non-existent or done in a good way. The rest of this might get a bit vague so keep that in mind. Most of what you see in the Warframe shop is something you can grind for. Or just in general attain via regular drops. I’m not saying they need to make a drop system, just a means to normally attain them without opening your wallet. Maybe if you do a challenge you get a sort of random lootbox, non-predatory of course and no repeats, perhaps what item you get corresponds with what armor core you’re using. However, this would likely trivialize the battle pass, which I think should only be reserved for events, which could be where a person gets EXCLUSIVE pieces of armor and a specific core. Probably put more in the event passes rather than small meaningless boosts or swaps. And of course a means to buy it if you get impatient. Hell, you could make the store into a large catalogue of various pieces of armor, categorized in the sections they correspond to. You’d make WAAAAY more money because everyone can buy something whenever they please, instead of frustrating your consumer because they were a minute too late to buy the set of armor they wanted. And before someone mentions it, yes, Prime Warframes are probably the worst part. Absolutely hell to grind but you can easily bypass by simply buying (say that ten times fast). To that I say: Don’t take inspiration from THAT. That’s what you wanna AVOID.
Customization:
So, issue with taking some inspiration from Warframe of course, is in the customization. My comment about the stuff within. Most stuff in there, is the cosmetic stuff. Which, in Infinite’s case, is it’s worst part. Silly armor, fine, sell it. Serious armor? No, let us earn that, and, if someone’s impatient, buy it. Moreso, I meant in the case of colors. I ain’t gonna repeat what’s probably one of the best Infinite posts, aka https://www.reddit.com/r/halo/comments/qxyw94/a_compromise_that_works_for_everyone/ so I won’t repeat what he’s already said. It’s a good idea, but TL;DR, give us a normal selection of colors, but sell different armor patterns, textures, and alternative colors. Like, different levels of hue, or saturation, etc. Although his definition of a coating pattern is different from my own. Probably. Basically Scorpion Punch is something I consider a pattern.