Question about void crystals

Why they are not doing anything about exchanging void crystals like all others armament crystals?Lets make a simple calculatin how long it will takes you to equip just one hero with 6 lvl 12 voids.You need exacly 4500 lvl 8 to synth 6 lvl 12.You can buy only one during Angel party event-that means 7 per month/84 per year.So,to have 4500 you will need 50+Years just for one hero!!!Most of us won,t be alive to do that..Ah,yes-and 354 years for all 7 heroes.Can you tell to devs,that we are not turtles-humans can,t live that long...