Honestly, if I had it to do all over again I wouldn't have gotten Marans... but just my opinion... they're not aggressive and my roo is a big dork/baby that the Silkie roos beat up, but they're very stubborn and will push around more gentle/timid ones... they're just not what I'm really looking for in what I like...
Sussex and Dominiques I know absolutely nothing about... Sally Sunshine has Brahmas, I'd ask her about those... Cochins have a good reputation... Orpingtons are great broody's from what I hear... I only have a roo with some Australorps right now, but they mingle really well with other breeds... and my friend raises Orps, says they are the best for brooding, not the brightest, but great setters and mamas...
Hope this helps... and if anyone else has different experiences/views, please chime in...