If I may say something different: the biggest frustration is not being able to use ZCash to pay directly, i.e. without having to convert to Bitcoin first, through whatever means: "PayPal" like service, ZCash Credit Card, etc. Yes, some exchanges like Kraken allow deposits to banks but it's defeating the purpose of why people want to use cryptocurrency.
My concern with "mining to a bank account" directly is that even if you go direct from ZCash to Bank, you'd have to eventually deal with bank transfer fees as well as currency conversion rates, plus the delays involved in transfers. In essence (and I understand that's probably how you envision the service) this makes sense only when large enough transfers are involved. Folks who are mining and have a send threshold of 0.01 or 0.1 ZEC are going to have to rethink that because most of their mining income would be diluted by fees (obviously).
The major break to adoption of such services is the lag time involved: if I want to leverage my crypto, I don't want to wait 2-5 days for a bank transfer to complete. Another issue (but one that whoever deals with bank accounts/SEPA transfers has) is the problem of where the funds come from and the whole (IMHO legitimate, but ouf of topic) legislation about KYC (Know Your Customer) and Money Laundering.
I'm sorry if that doesn't frames exactly what you are looking for, but hopefully that helps.