I was thinking of improving Overdrive…
So here are my ideas:
When reaching a high power level like 
30, overdrive can be boosted; instead of firing 50% faster, maybe increase the rate to 80%.
A new item in the shop: Hyperdriver - doubles the rate of overdrive-firing for 30 overdrives or 1 mission. If the developers decide to make it last for 30 uses, then the cost might be 5🗝x 30. If the developers decide to make it last an entire mission, then it might cost 120🗝.
Overdrive is a good feature, but it does have room for improvement in some cases. Weapons like the Neutron Gun have a decent overdrive rate, but people who collect a lot of firepower after 20 might find the weapons too much of a bore in the end during long missions. And I do understand that the BX-9 Mjölnir has a firepower extender to 50 or something (I never got my hands on that ship), but other people who use spacecraft like the Muller M-404 Pi Caterer or H&C 301 Cockerel might want this feature.