Halo 2 > Halo 3 > Halo 3 ODST > Halo Reach > Halo CE
Based on campaigns.
Posted by: Watson 203
I don't think much canon has really been established on Covenant species homeworlds.
Generalisations have been made such as deserts on Sangheilios (Sangheili/Elites), methane swamp/marshes on Balaho (Unggoy/Grunts), and what you stated about Doisac (Jiralhane/Brutes). Sangheilios has probably been the most explored of them all.
The only way to find out more would be to ask at conventions if you go to any. Your next best bet, and the most easy method, would be to look on something like Halopedia or Halo Nation, read up on what they say, then look at any artwork and make your own judgements based on the pictures.
Like I said, because not much canon has been established the only judgements you can make are your own based on what little information we have.
One final point; there may be some information in Halo: Glasslands or that trilogy of books as they are released. I haven't read Glasslands, yet, but I know the book explores Sangheilios. With that in mind the story may explore Doisac as it is the home planet of the Jiralhanae as you stated and the Sangheili are at war with them. But that's just an idea.
EDIT: Sorry i'm kind of repeating some of what has been said. When I first clicked to make my post, nobody had posted any replies. I spend lots of time proof reading. Yeah.
Thanks, I suppose you are right