I think railjack shouldn't have released with basically 30 extermination missions, but instead only a few of them and then expand the missions gradually in a consistent pace, with a lot more variety, such as different mission types and locations. And along with those new missions, gradually introduce new upgrades for your railjack.
Right now, what we have is a fun mode with a lot of potential but is incredibly repetitive. After playing a couple missions, you've basically seen the bulk of it. Taking out the same fighters and crew ships quickly gets old. I haven't progressed past earth, and I'm not looking forward to do so.
We were promised a lot more variety, but we still haven't seen or heard any of it. What happened? I feel like development has bogged down (which goes for Warframe overall as well).
I get the feeling that it's not really going so well with DE.
Next, why do we need someone onboard the railjack to manage resources? Who plays warframe to refine resources and craft stuff while on a mission? Maybe it's just me, but how boring can it get?
You know what might have been cool? Go into a mission where you rescue a vessel from a grineer attack. After fending of the ships on the outside, the entire squad can enter the vessel to clear it from hostiles. Basically turning it briefly into a regular Warframe mission. After that, the squad moves back outside and fends of a next wave of attackers so the vessel can repair it's engines or whatever. Then escort the vessel to safety.
The stages could also be randomly combined, so it doesn't get so predictable.
I really hope railjack can become what everyone imagined it to be.