As PG suggests in one of his essays, I'm "digging a hole that's narrow and deep". I'm targeting a few thousands companies worldwide. The business area they're in is fast-growing and fast-changing and I suspect that they might be wary of adopting innovative solutions because they don't have clear ideas about where their own business is heading. Some don't even seem to have clear ideas about the prices of their own services and products (I tested this hypothesis by offering a simple, free tool to help them model their costs, and the feedback has been clear and positive).
I wouldn't say there's a risk of regret: I'll certainly regret it. Presently, apart from my mental exhaustion, I'm in pretty good shape, both physically and financially, but I need to set limits and draw lines. One of my main worries is that I cannot figure out what's not working, why I cannot get more clients on board and why it's taking so much time for them to go live. I developed the app at blazing speed and now the sales are going so slowly that it looks like nothing is moving and I find that unbearable. Maybe I'm just missing some entrepreneurial skills? I wish I knew which ones. Right now, I would just like to get rid of the whole thing, as irrational as it may seem.