Excellent post, as mentioned it would be easy to acquire the necessary talent pool in London. However, just starting out on the tech platform would have a significant price tag attached which means funding would be necessary even without a MVP....hard if not impossible to find
Automated functions, like storing money, transfers, (digital?) check processing, buying indices - all on explicit commands and with fees - even storing money - but dirt cheap.
After that we can talk about less clear-cut functions, like various kinds of investments or loan offerings.
I would ignore checks. Here in the UK, they're hardly used anymore.
This was my rejected idea for Ycombinator. I still think there's a lot of potential in this space, very similar to Simple.