I'd prefer to see the 3e psionics come back. I loved that you could take the charm ability, and then pick and choose by spending power points who it worked on.
Psionic Charm
Initial cost: 1 power point
Additional cost: 2 power points to be able to affect animals, fey, giant, magical beasts or monstrous humanoids
Additional cost: 4 power points to be able to affect aberrations, dragons, elementals or outsiders.
Additional cost: 4 power points to increase the duration to 1 day per level.
For every additional 2 power points spent, the DC went up by 1.
Now, that's the 3e version, so those numbers and effects wouldn't match up in 5e, but I think a toned down version could work.