Im bad at boosting.
Every so often, just do a little hop+barrel roll on a straightaway if you're getting too warm.
I also hate those Spike field things
The missile things? Yeah I hate those, I only recently discovered a strategy to deal with them.
Drive towards one angle and let the targeting lights start lining up. Then when you get really close, make a sharp turn away and kind of zig-zag until the towers are out of ammunition.