There is one GIANT flaw in your idea:
TacticSoft cannot make any profit out of those “Ultra Tokens” because they are not for sale for money.
So since TS cannot make any profit out of it you are asking them to create content that will not give them anything in return.
That isn’t gonna happen as a company always works to GAIN MONEY!
Also your idea of increased drop rates from boxes could be easily created without “Ultra Tokens” in a way that TS would get a profit from it.
TS could simply add a special sale in premium shop like:
“Increased drop rates for the next 5 purchased premium boxes within 24 hours:
chance for legendary item increased by 5% - 100 tokens
chance for legendary item increased by 15% - 200 tokens
chance for legendary item increased by 30% - 350 tokens
chance for legendary item increased by 50% - 500 tokens”
The same for premium packs but with double the price.
That way TS can gain profit and players can decide if that additional chance would be worth the extra token costs.