5/50 mystic or save resources for 5*?

Vendemiaire

Hi, fairly new to the game. I'm pushing to become Uncollected.

My main roster:

2/35 Void
2/35 Archangel
5/50 Domino (Awakened)
4/40 Stark Spidey (Awakened) (waiting for 1 tech T4CC to be 5/50)
4/40 Iceman (Awakened)
4/40 Havok
4/40 Stealth Spidey
4/40 Warlock

My mystic champion roster:

4/40 Longshot (Awakened)
4/40 GR
Unranked Mojo
Unranked Scarlet Witch
Unranked Claire Voyant

Now, to the topic. I have almost 6 full Mystic T4CC. Should I use them to 5/50 one of my mystic champ or should I rather wait for a 5*? If yes, on who?