Now think about it. How much flight time it takes to get 100 perks?
Its not much better than the 12 hours thing. In an average 3 killer g6 sortie (20 mins) i get like 5-10. Thats (considering the idle time) is average 15 per hour, ergo it takes 7-8 hours of continous flying to get 100 perks... i give it a -1, im not midway. So fly 7 hours against the horde only to be able to switch? Think about it, it may be even worse than the current system...
What about a compromissum? For example, you can change once in 6 hours for free then 100 perks for the next one?