Make instant build like energy in events

Instant build could be energy related so the alliance unit training option is not a 5 percent5 but gives an amount of free time builds based on vip level. Vip level 21 gets 10 free time builds upto vip 27 gets 70 free time builds. After this 1 energy replenishes every 5 mins ( so you can get 1 more free build every 5 mins) this would mean players could goto sleep and wake up and build 70 waves instantly
This option does not get rid of instant build but instead makes it strategical when you use it.