IMO the vanilla the Selune's dream cantrip has very limited use, here's my take on it, trying to make it more useful but still balanced:

1 - Can only be used in combat
2 - Can be used once per turn (instead of once per long rest)
3 - Changes CON save to 13, the receiver needs to pass it in order to not sleep after the spell (original save was 10)
4 - Changes heal amount to d12 (originally was a d8)

This is my sixth Mod for BG3,  i try to make stuff that are fun and balanced, if you liked it take a look in:

Sacred Flame

Fencing styleHurry Up!

Tactical leader
Pact of the Blade Buffed