crawl VS crawl-ancient

It's probably not as rigorous as what you're thinking of but the devs of DCSS have cited online win rates of certain combinations as the impetus for balance changes before.

https://crawl.develz.org

In a similar vein, see Dungeon Crawl Stone Soup, a free and open-source roguelike that's been continuously developed by volunteers for 20 years: http://crawl.develz.org/

They are entirely too humanoid. I mean, look at these splash screens: Kiku, Ignis, Chei. While those images shouldn't be taken as canonical, they at least demonstrate the general inhumanity of the Crawl pantheon.

Since you like turn-based games too, try some old-school roguelikes. Many are open-source freeware so you have nothing to lose but time. I've been playing Dungeon Crawl Stone Soup for almost 10 years.

Since Brogue's already been mentioned, I'd add Dungeon Crawl Stone Soup and Tales of Maj Eyal as pretty beginner friendly games.

For people who don't follow trunk, Okawru's gifting has been changed (and arguably* nerfed):

My personal first timer recommendation? Maybe Nethack or Dungeon crawl?

Dungeon Crawl Stone Soup - Free traditional roguelike with fair mechanics and a lot of variety between species/skill/god choices (~25 gods and maybe with the exception of sif/veh and oka/trog, they are very distinct). The tiles are great. There's many developers and they are very welcoming of code or vault contributions. Reducing incentives to play tediously is one of the goals. Easily hundreds of hours of gameplay for free. Playable online (connecting to a server through your browser/terminal) or offline (terminal or tiles version). There have been win streaks of 50+ games with a variety of species/background combos so you know it's mostly fair(it IS possible for rng to give you an unwinnable game), but it's very difficult if your goal is to win every game.

You can check out Linley's b26 on github, where that wasn't a thing, or you could checkout the 0.11 tag in the DCSS repo, where that still wasn't a thing.