Insurance is less of a problem than banking. Federal regulations still say what we do is drug dealing. Try calling them anonymously and asking about banking cash from the sale of medical marijuana. I'd be pleasantly suprised if they said "come on in".
The feds taking your tax dollars has no connection to banking. The feds expect tax payments on black market income, so they would definitely want tax payments from gray market medical cannabis sales. I'm glad you have a bank account though, and i hope the bankers never find out where your money comes from. I'm pretty sure they'd close you down stat.