I'm mildly annoyed that I'm met with a "Book a Call" CTA when I click the Accountants tab, but I get it.
I think the feedback re: Excel preeminence/stickiness and outsourced workflows is pretty indicative. Similarly, I, too, am curious about the long-term commitment you're willing to make, considering the prior pivots.
That said, this looks clean, and I plan to check it out. I'm doing some work with a fractional CFO firm and I'll recommend they explore as well. Working within a built-in spreadsheet could very well provide the right level of flexibility -- especially if I can access them via the API for downstream manipulation (I haven't looked at the docs yet).