I've kept a few chickens over the years so I'll chime in here. I have kept Wyandottes, leghorns, seabrights, Araucanas, Rhode Island reds, etc.
By far the most productive bird I have kept is the white leg horn - smaller bird and easy on the food cost and consistently lays a nice large white egg - but kind of a boring hen from a color standpoint.
Araucanas lay a greenish blue to blue eggs which is a fun novelty, but they are less consistent as an egg layer. The roosters are very attractive color wise.
The wyndottes have been the most broody from my experience.
The brown leghorns, rhode island reds and wyandottes all are brown layers and are fairly consistent.
As for rooster disposition, I haven't kept enough to see a good or bad pattern by breed. I've had mostly good disposition bleep and just a few ornery ones. Although my daughters might disagree. If you are on the smaller side the roosters seem to size you up and think they can take you on, until you show them who is boss.
BlueBird , you asked about the attention they need...for our set up it is pretty much daily feeding and checking on water, though I think some people are set up with feeders that might need refilling every few days. On average I spend about five minutes a day feeding, collecting eggs and topping off water if needed.
My biggest problem is coyotes and skunks. I have lost too many birds to these thieves. I plunked a skunk earlier this summer that killed six hens - aarrrggghhh! :evil: