I've made lots of films over the years - there's currently 9 camera mounts on my Pitts and 10 on my RV.
If I had to choose only one for producing the most consistently interesting footage it would have to be the one on my headset.
After that, the center top wing on my Pitts - which has inflight tilt & pan via a couple of R/C retract servos.
Some examples .....
Have fun - I think video making is the next best thing to actually flying !