TL;DR: Archwing's fundamental level design and philosophy is terrible, restrictive, and underdeveloped causing players to not wish to engage with the gamemode at all causing it to become depreciated and see fewer expansions and changes that would make it a legitimately good game mode, This bled into Open World with the blink debacle and Railjack with Amesha being the only one to not get one-shot or perform well. Proposed solution: Make new and better archwing tilesets and missions, overhaul uranus, and properly balance the archwings against the gamemode, and the gamemode against the archwings
Archwing exists in only 4 contexts:
1. Open World
3. The Balor Fomorians
The third one is its main focus, all dedicated archwing nodes on the star chart have the Balor Fomorian looming in the distance. This focus on the conflict the Balor Fomorian creates intrinsically bottlenecked design for space missions to only two types of nodes: An asteroid field with few major obstacles, and a destroyed corpus ship with extremely awkward level design and very difficult and tight obstacles to navigate around at high speeds.
The fourth one introduces a different problem, the archwing feeling slow and clunky in a claustrophobic low visibility space with homogeneous rocks taking up the backdrop, making for very boring, hard to see in maps that are easy to get lost in because everything looks the #*!%ing same.
These two contexts are the apparent meat of archwing, as they are the dominant forms it appears in on the starchart, and they are fundamentally terrible. We shouldn't only be going out in space to scavenge the remains of a fomorian attack or disrupt the fomorians, and the caves should be more spacious to allow more speed and have overhauled visuals to not be so easy to get lost in. Imagine raiding an active Corpus docking bay, disrupting a fleet of Grineer Galleons, or exploring the seas of Uranus. Pie in the sky ideas that would take a lot of work to realize, especially in the face of currently promised content, but would be infinitely better than what we have of "destroyed corpus fleet" and "grineer asteroid mining operation"
Archwing has always been a good idea for warframe, and is not a fundamentally bad gamemode. The problem lies in the fact that the design philosophy was too restrictive, and the levels that were designed were simply bad, especially since there are only 3 effectively. What Archwing is now being changed around is essentially side uses for archwing, rather than these side uses conforming to the meat of archwing. The archwings should be changed to feel more powerful within the gamemode, as well as the side uses. Not completely ignore the gamemode and suddenly have all the archwings be godly in it because they're designed around enemies dealing damage in the thousands at base, not enemies dealing damage in the 10s or 100s at base.
Odonata is the Jack of No Trades, Master of None, being markedly awful at everything it tries to do. Energy Shell should prevent blast damage from bleeding through and have a more visible indicator of what it can block and how much it can block, and homing missiles should be more powerful.Itzal just needs a numbers tweak, really. Elytron needs all of its missiles improved drastically. Higher damage, faster speeds, larger blast radiuses. It should feel like the dps wing, not pre rework ember. Amesha should also have more than a decoy and a god mode button. I haven't played with it enough personally to know what to do for it, and someone else I'm sure has a plethora of ideas of how to make Amesha more interactive than a god mode button, but the fact that invincibility is what makes it good is a very big problem, all archwings need increased base armor and health if it's that bad. Also, Archwing needs more mods in general. As it stands there's not enough mods for any build variety what so ever. Something as simple as corrupted archwing mods would go a long way.
These are changes I'm sure would have been made if Archwing saw further development and was not abandoned by the community due to the terrible tilesets. Archwing needs to be enjoyable to play, and the absolute core of that is the level design. If the levels were fun, people would want Archwings to be better and more fun, not abandon the gamemode as a mistake, and only remember archwings exist for side objectives where it was used better than the original missions. The Archwings are great, and the gamemode is intrinsically fun, but that fun is hamstringed by the level design completely since we crashed into that same wall 6 times trying to blow up all 3 of those corpus cargo ships in time