Yes, I was going to say the same. If one is into the avios world, it would be helpful to know where to credit as there are so many inconsistencies.

I recently got bitten, having my QR number on a AA boardingpass for status perks without checking the earnings. So it turned out that the fare earned zero avios on QRPC while BAEC was a good payer. In my case peanuts but still annoying.

The challenge for you would be to keep it up-to-date. I think earnings might be tweeked alot over time.

Also, what I find tedious with existing services is the manual entry. Many fly a lot, and many tries multiple options before booking so repeatedly entering multiple datapoints will hamper.

It would be nice if you could just drop text into a box and it would be analysed by your site as to what is what in the fare. Different programs counts differently what is part of the spend that earns. E.g. I think IB counts VAT as part of spend and AY doesn't (to the best of my understanding). IB also have other quirks, eg they combine spend based and route based earnings on some routes.
These differences is a major obstacle for those of us who no longer enjoys keeping too many details top-of-mind and handling of all that would be good feature.