I think that I'm a bit biased on the breeds, (we all probably are) but I want to start off by saying that not ALL breeds are like the label we put on them. For example, I wouldn't ever recommend the Netherland Dwarf for new rabbits owners or ones with little kids, just because they can be stressed out easily and often times the breeders won't socialize the rabbits enough, so they're always skittish. But, if I did have the sweetest ND, whom I know handles stress well and would be a good fit, I of course would offer that as an option. Breeders are another topic I want to discuss, but let me finish this. For me personally, I find larger breeds are more of a couch potato, and smaller ones are more curious and adventurous, needing more exercise. And larger breeds tend to have a sweeter temperament. I love the Velveteen Lop, I find them so personable and cuddly. They're pretty much like a puppy dog in a bunnies body, temperament wise. Now I have had a MEAN V-lop, who wanted absolutely NOTHING to do with you. I also currently have a young Mini Lop/Holland Lop mix, who is just about the sweetest most cuddly thing in the world. When she was smaller, we'd stick her in our shirts and carry her around to keep her warm. She just sat there and slept. Cutest thing ever. Her mom though, was quite shy and hates to be picked up and touched. (Mom is a rescue off the streets though, baby grew up with us spoiling her).
Now for the breeders, I would always recommend buying a bun from a breeder that says something like 'breed for quality, not quantity' or 'breed for temperament'. I find that smaller rabbitrys have more socialized buns who love human attention. Now, if you're adopting, of course the temperament of the rabbit is really the only way to tell, you can't much rely on the temperament of the breed, because of their backstory and things they've been through.
But you are right when you said that its the personalities you look for. If you find the sweetest little Dwarf bun, go for it. Or even the snuggliest Flemish! It's really all about the rabbit.
Good luck!