Themed spell lists can work well. I'm currently playing a half-elf bard turned sorcerer, who's focussing on enchantments and alterations. A few key spells (plus Extend and Chain spell feats later!) make him pretty potent. Core spells include:
0. daze
1. charm person, sleep
2. blindness, detect thoughts, tasha's hideous laughter
3. hold person, suggestion, tongues
4. charm monster, emotion
5. hold monster, rary's telepathic bond, sending
6. eyebite, geas
...
I've written his ancestry as bronze-dragon (who have mainly mind-affecting spell abilities w/ lightning or repulsion breath). This character's diversity comes from liberally adding lightning-based evocations, or shape-changing spells for his "extra" spell slots.
Of course, push him off a cliff and he's lands pretty hard
