Everyone has different liking & preferences. You are the best person to decide which is best for you. You can do this by adding Flightaware to your setup. You already have Flightradar24 setup. Once you have both setups running on your Pi, you can compare the two.
.
.
.
YES
Please see these threads:
(1) How to Feed Data to Multiple Sites - A Brief Guide
(2) Bake a Pi (Links to “Option-1”, “Option-2”, “Option-3”, and “Additional Data Feeders” are broken due to migration to new forum. Scroll down to next posts to see these).