I here that 343 is going to revamp, Halo 1, Halo 2, Halo 3, Halo 4 and Halo CE for the PC. I think that would be great. My only concern if they remake the games like they did the original versions. Example: Halo Combat Evolved. They have a server browser, Forge to make maps, ( there was a 3 party map editor called Sparkedit back then ) To be able to run you "OWN" game server like in the original and Not adding these new lame rules like getting banned for leaving in the middle of a game.
If Reach is any indication, a lot is going to be changed and they will barely be true to the originals. As for a server browser and hosting your own server, I think the chances of that happening are as close to 0 without being 0 as you can get. This is 343 we are talking about, they just do whatever they want and if you like it cool, if not tough luck we ain't changing it. I would expect more of the same from what we have seen with Reach. I'd also bet my left nut that the same leave penalties currently active in Reach will make its way into the other titles.
Personally I lost all faith in 343 when Halo 4 came out, and with Halo 5 I like to pretend the 343 made Halos don't exist. It hurts less that way.