I agree with you in that I actually enjoy the Archwing missions (I also like Railjack) and feel that the issue isn't removal, but a re-examination of them. Most of the Archwing missions content hasn't been looked at in years, and in that time, the game has changed enough that it would be worth taking those "lessons learned" and applying them.
I also agree that the Archwing weapon parts should not just be limited to syndicates/clans. Make them rare drops or a reward for certain missions. A steady path of progress is what drives players towards content.