So, semi-new DM here. My group & I have played about 16 sessions. They're just now beginning to hit level 4. I've been playing Baldurs Gate 3 and I learned something that I overlooked in the player's handbook. Warlocks regain spell slots from short rests. I have a warlock player at my table. She's always played super conservatively with her spell slots, and I feel bad now.

So, what I'm considering doing, in addition to playing properly going forward, is to give that player this ability, next session:

"Stored Power: You may spend a bonus action to restore a single spell slot. Once you've done so, you may not do so again until you finish a short or long rest. Once you've used this ability 4 times, you will permanently lose access to this ability."

Any and all thoughts / suggestions are VERY welcome (feel free to suggest alt titles to the ability as well). My goal here is to give her back some of her missed power, without all at once making her super overpowered. And again; about 16 sessions in, and she's about to hit level 4. For context of how long this error has been going on.