I have most of the breeds you mentioned. I've never had Orloffs or Marans. I wanted dark eggs, but read that the marans weren't great layers, so I got Welsummers instead. My Wellie girls are great layers and all around nice birds, right in the middle of the flock, same with the Sussex, Rocks, Orps and Australorps. My Easter Eggers were as others described, super flighty as youngsters but calmed down as hens, I love the variety of them...they come in so many colors. I like having a colorful egg basket, so can't imagine not having them. My experiences with Wyandottes have been hit or miss. I had a GLW that I loved, but she was a bossy girl. I've had a half dozen Blue laced Reds that i got from Meyer Hatchery and they've been lovely birds. The Silver Laced ones I got from Mt. Healthy were just mean and I gave them all away just to be shed of them. I'm new to Barnevelders, just got some this year..they're about 12 weeks old now and they're really sweet, calm birds, and I had no idea that they were such attractive birds, they're quite striking! I can't wait to see what color eggs they lay. Every year I try to get a new breed that I haven't had before, my criteria are .... Must be good layers and do well in a mixed flock. My experiment this year is Faverolles. So far..they're quite submissive....chicken littles of my flock..we'll see how they do.
If I had to pick one breed that was my favorite, I'd say it was my speckled sussex. They have such funny personalities..they're super curious and talkative, always entertaining. I will always have them in my flock, in spite of the fact that they lay smaller eggs than the rest.
Edited to add - In regards to Roos. I have a great Blue Orpington roo. He's always looking out for the hens, calling them over for food & treats, breaking up squabbles, he has not shown an ounce of aggression to humans ever. I had another Orpington roo, he was HUGE and was a sneak attacker. He'd wait until your back was turned and then attack you. I put up with it for awhile, tried the usual tricks to discourage it, then one day he put a hole in my husband's leg through his jeans even..and I got rid of him. I've had an EE roo that was great too, lost him to a fox though, and a Speckled Sussex roo who was quite aggressive and is no longer here as well.