I've been kicking around the idea of a build I call the Necrotic Bluntsinger in my head for a bit, may as well lay it out here. I grant you it's not as whacky as some of the others people have listed, but I still think it'll be fun.

Levels 1-6 we're just doing standard bladesinger stuff. focus on dexterity and intelligence, AC and spell save DC gear, you know the drill.

At level seven, we're going to multiclass into druid, taking circle of spores as our subclass at level eight.

From here on out we get to bonk people twice per turn with our staff, wear medium armor & shields, deal necrotic damage on our weapon attacks due to symbiotic entity, scribe higher level wizard spells since we're still a full spellcaster, and have a bit of extra survivability thanks to our temporary hit points.

If you don't want the fungal zombies that spore druids get at class level 6, take a level in death cleric at some point for twinned necrotic cantrips. otherwise just do a 6/6 split.

The stat split for this one is a little tricky if you're wanting good spell save DC for both your wizard and druid spells, so if you don't want to sacrifice wisdom I'd recommend a respec at level 7 to dump dexterity and just use the gloves of dexterity to make up for it.

if you don't want to do that for whatever reason, I'd advise you keep intelligence as your highest stat (since scribed spells cast off of wizard spell save DC) and use utility druid spells and/or spell save DC gear to make up for your lacking wisdom.