Hopefully, the new sats will take care of that for next year. It is a bummer once you get used to watching a game in HD to have to watch it in SD! (I've only had HD for about a month and MAN have I gotten spoiled!)
The decisions as to which games will be in HD is based on interest and importance. If your team is having a less-than-stellar season and there are games which have better teams (especially as we get later in the season), regardless of size-of-market, that is how they decide.
I am also hoping that the quality of the picture improves once they have more sats available and they can reduce the amount of compression. Right now, sports from the HD locals in mpeg4 is pretty bad! The Sunday Ticket channels look pretty good though.