100% Alakazam

I have a 100% IV Alakazam at level 24.5 now. He was evolved long ago from a hatched Abra, even before the CP rework. He had PC/DG (now legacy). I gambled with charge TMs with him for the sole reason he is 100%, and got Futuresight in 2 attempts.
He is my only 100% mon currently that has even any use in the meta.
I already have a 84% PC/ShB Alakazam at level 30, and another 91% PC/FS at level 20. I also have a 86% 15 attack ZH/FS Espeon at level 28.5.

I really want to max out the 100% Alakazam, but I'm afraid he will be a waste of stardust and just sitting in my inventory.

So, should I:
1: Power up the 100% Alakazam (if yes, to what level, or max)
2: TM any of the Alakazams or Espeon to Confusion (now I don't have any Alakazams or Espeons with Confusion, I didn't TM away confusion)
3: Power up the Espeon, or the other Alakazams?