Well your other options are (off the top of my head) Whitefields, Benefactors, Cryfield and Westwood.
Whitefields are halls dressed as houses essentially - there are 17 of them, each house about 12 people. They looked quite fun as far as I was concerned, I imagine it feels a bit Big Brothery at times but as long as there are good people in there I think Whitefields has the potential to be the most enjoyable halls. They're just in front of Rootes, so very close to the gym.
Benefactors only accommodates about 70 people (of which 48 are in shared rooms) so you'd be very unlikely to be put in there as a 3rd choice.
Cryfield is the cheapest - the atmosphere in there is supposed to be pretty good, but the rooms are very small (on the plus side it does have separate common rooms, unlike Rootes).
Westwood is roughly the same distance away from the all the central stuff as Lakeside and Heronbank - it treats itself as a bit of a separate community, though not in a way that isolates everyone from everything else. A lot of the sports facilities are on the Westwood campus, though not a gym as far as I know.
And accommodation isn't first come first served. As long as you've made your choices by July 31st you'll be fine.