If you want it done properly, do it yourself!
That's what I did
Chembuddy is taking care av the stochiometry, and thats fine.
+solutions +concentrations +buffers +pH
But I am thinking seriously about chemometrics and taking care of large collections of data.
I think there are statistical programs (some open source) that will deal with these things. Could be it is better to invest your time into making these tools better, than to start new ones from scratch?
That's not to discurage you, but most of the separate projects die sooner or later, many of them never getting mature. Time down the drain.