If you view this as a temporary situation, I second the idea of starting by changing your rear casette. If you ride shimano, you can go all the way to a 12/27. The advantage of this is you can swap casettes quite easily as terrain changes or you get stronger, and it involves the minimal parts swap. Yes, you *may* need a new longer cage rear derailleur, but you may not. My husband has a standard durace short cage dearailleur and I think I replaced his 11/21 with a 12/25 with not problem, except of course for needing a longer chain. Do you race? I use a long cage rear derailleur for everything on my bike, and just swap casettes for changing terrain. I personally don't find that I even notice wide gear spacing until I move to a mountain casette (11/34) and even then, its worth it if I have serious hills to climb. Another advantage of larger spacing is you need to shift between front rings less frequently, big ring for flats, small one for hilly terrain.