Subscribers don't matter! If you have brand awareness and ready product, then you can compete with other product and people will be telling about you, so don't pay attention to social network
Yeah, If you saw one ICO project Youtube account with thousands of subs with only a hundreds of views its only meant one thing, its a bounty or they pay bots to inflate their numbers.
Having 160 subs is normal for any ICO projects, What matters is its growing organically.
Are you going to increase fee for getting this card? How much do you earn annually on each client and what is price to attract 1 new customer? Do you have such info?
They sell the card for $10 each, They earn thru deposit or funding fee's