High Priority changes
The Derelicts and Corpus Outposts need to be overhauled to fit the new aesthetics of Deimos/Isolation Vaults and Venus/Corpus Ships. They are woefully outdated tilesets, along with their enemies. Swapping in the Deimos Infested and Corpus Ship units (though preferably Orb Vallis units) would go a long way toward making those locations relevant. Adding voice lines for each location’s “syndicates” would also be a bonus from a narrative perspective.
Also, it would be nice — but not a necessity — if the Necralisk and Fortuna had the Relays’ Navigation features, but specific to Deimos and Venus. It wouldn’t need to be a direct tunnel like the Crysalith or Sanctum, but a way to get from the hubs to the missions would be a good quality of life update.
Medium priority changes
Assassination mission tilesets in general need to be a bit more unique compared to the other nodes. Without making them more complicated, the missions as a whole should feel more like you’re heading into a boss fight. This needs to extend to more than just one tile.
Low priority changes
Phobos: It’d be nice if Phobos could get its own tileset one day. Personally, I think the Sanctum hub and tileset would have fit better on Phobos (given how distinct it is from the Necralisk aesthetic), but regardless I think Phobos could use its own distinct look and personality. Maybe a Corpus asteroid?
Mars: I really wish the Grineer settlement tileset would get an overhaul, not just a lighting rework.
Earth: I think the Grineer forest could benefit from a bit of a visual refresh, at least to bring it in line with the intro Awakening quest. It’s not a huge difference, but it is a bit better and makes it fit a little more with the Cetus environment.
Pie in the Sky changes
Not so much a tileset change as much as a star chart change, but I think the following changes would be neat:
1) Break up the Orokin/Void Tower branches. There are already four branches that connect to different planets/moons. Instead of having the Void in one location, put those branches next to the planets/moons they connect to. Furthermore, we have at least three different styles of Orokin architecture now (Lua/Classic Orokin, Cetus/“New” Orokin, and Deimos/Entrati), four if you count Duviri. It would be neat if each different Void Tower branch reflected a different style.
2) This is a bit of a three-parter: A) More Empyrean Proximas: Mars/Phobos, Europa, Ceres, and Eris would be great, especially if Mars/Phobos was Crossfire and Eris was Infested. B) Since Empyrean missions exist, it would be neat to convert Archwing missions to surface level missions, with similar gameplay features as Empyrean missions. C) The Balor Fomorian and Razorback Fleet invasion missions should be overhauled to be like Empyrean missions.