Incursion is pretty cool. There are a few wonky design choices (I'm really not a big fan of the inventory decision to be 'holding' an object, and forced to swap it with whatever you are equipping), but other than than it is quite cool. Character customization is immensely deep, with a really good implementation of the D&D3 (maybe 3.5?) ruleset. A few thing were changed to make them work in a roguelike, but they were good changes.
I have to admit to not being very good at it - it seems quite hard to me, and I have ascended a few characters in Nethack. I definitely applaud the creator - he has done a great job, and deserves a lot of credit.
As Corremn mentioned, Crawl Stone Soup is good too. I find it a little bit dried than most rogues (well, anything is after being tainted by Nethacks goofy gameplay). The playstyle is a little like Angband, in that it's more aimed at combat than anything else, and it does this really well.