Type of instruction symbol/icon
I think it would be helpful if there was a way that a flight school could mark a student's reservation with a symbol representing what kind of instruction the student is doing.
For example, perhaps a letter in the corner corresponding to the following:
B - BFR
P - Private
S - Sport Pilot
I - Instrument
C - Commercial
M - Multi-engine
and so on. That way, instructors could look at a glance and see what training they are doing.
Ryan Tingley commented
You may be able to get a similar result by creating different activity types. For example, create a "Dual Flight Training - Sport" and set the color to be shades or orange, then a "Dual - BFR" and set colors to be shades of blue, etc. Then each color set would match the training type.