I've noticed that there are 3 height levels of jumps depending on the press on the jump button (I prefer the spacebar):
1. a mini-jump alowing to skip a crate but still continue running.
2. a medium jump is good for windows that are lower then the platform.
3. a high jump: the regular jump we all know.
i know soultwister already suggested it but i got one more reason why suiciders in survival should count as a kill for you: in the end of the survival it says challengers which means opponents and the suiciders count. also another suggestion: make a general option to dsiable shield for everyone because i hate it when i shoot a homing missle and they shield for a second and don't die.