There can be pits, the code does exist. I did plan that some ships would be fast, but would be unable to recharge, or that the energy starts to drain down as they start to race.

In my design document I did also think about having a variable power shot (sort of like R-Type) that uses varying amounts of power the longer you hold the fire button.

Instead of an EMP, how about a jamming radar? It would act like the vulcan autocannon in that the beam of energy would lock onto an enemy ship and jam its weapons- it could be possible to copy the leech cannon too this way. This would also be good as a balance to stop fast ships from having too much of an advantage (since they would need to stay out of the way of larger ships).