I would give you a lot of roster help, but these guides below cover most of it. You’re working on the right path. A couple things I would say though.
Change all except Psylocke's obelisk. Get either invincibility obelisks (ones which say invincible (x seconds)) or damage procs like Psylocke’s one
Change all your ISO sets to either attack or shield sets. Most of the characters need attack sets anyways. Always roll for 8 ISO sets. Also check your characters base attack stat. You find it through Team->Any Character->Under Level it says energy attack or physical attack. I noticed Luna and Psylocke have physical attack ISO equipped. I would suggest, since you’re a spender, unequip those with crystals and equip the right ones
If you want any more help, PM me through Reddit or check my account. My IGN is Only Legend. (I’m a F2P player and I stopped quite a few times and carried on). I tried adding you as a friend but I couldn’t. If you play actively or semi-actively, add me please. Also, if you know anyone who plays, I need more active friends. I’m going to start working on my brother’s account soon.
You need to use a high DPS character, there are many of them, for me I used Psylocke. But most importantly you need at least two "agent" allies such as Black widow and Kate Bishop, they give ignore dodge by 20%. Upgrading raid level would help too.