Some of the requested features "scare" me on your behalf, Dave (grin).
• Doppler correction information (1) • Footprints (2) • Satellite information including frequencies, modes (5)
If invoked, you will need to update the program VERY often ... because if there's a mode change on a sat, and your program doesn't show it - well, that's the type of "support" email you do not deserve to receive.
Personally, I would make people perform their own research for the satellite control operator pages, and get the freq info in that manner. Otherwise - to be accurate - you will have to edit your program every mode change of a sat.
I see your program (and the other good ones) as being tools to tell us WHERE the sats are. Get that aspect of the process down reliably and painlessly - then you are "ahead of the curve" from other lesser programs out there. I truly believe it is up to each ham to educate themselves on how to find the best info on freq/mode data elsewhere.
Clint Bradford K6LCS