Honestly I'd hardly call being given 4000 acres where 35 miles of trail already exist a big issue. We are currently fighting for every miole of trail we can get. We have a total of 8 miles of sanctioned Mtn biking where I live and that is split between 2 parks. We were just given 400 acres (1/10 what Fruita was given) and we are tickled pink.
Work with what you have. They didn't take anytyhing away. With 35 miles of trails and the traffic it sounds like the trails get I woudl say a bigger concern of mine would be proper maintenance of existing trails.
Good luck with getting more land but don't lose sight of what you already have.