The Rocket Launcher may also be used to gain speed on straights; it incurs soft damage, so there is a limit, but even just getting a few well timed blasts directly behind you, you can get you from 200 to around 350, from what I remember.
The TB spam is a bit of a cheaty way to get over the straights, but speed > distance travelled. Its greatest use is changes in height as it's harder to do that with a jump - TB has far greater reach.. so try using it on the last point, in the base asteroid, on the bridge to zap up there and take that flag while retaining all speed!