Actually, at the moment I would prefer, actual time / height / climb rate data. If we want to write this software, we need to know how our flights "look-like". (We need to "teach" the software to relate info to our flight plan(s) )
Forgive me asking an obvious question, but do your two Cessna Caravans have ADS-B and/or ELS and/or EHS ? And do they report altitude in 25' or 100' increments ?
Depending on the answer, there are several possible solutions.