If you can play a recorder in C then there really is no excuse for not playing one in F correctly. Any difficulty is all in the mind - as someone who has taught recorder professionally for nearly 40 years, I would start someone off with 3 note exercises (tuneful ones!) but say: "I am only going to give you the fingering for the first note." They will play the first note, see that the second note drops a tone and automatically add a finger. By the second week they are very comfortable with 5 note tunes and the third week they are playing a full octave. This is for 10 year old kids. Easy peasy.

Someone mentioned ornamentation being tricky in outlandish keys - to a point, yes, but don't neglect alternative fingerings which you pick up as you need them. For example, say (on a C recorder) you want to play an upper mordent from D# to upper E - D# is what I call the 'mid 5' fingering while top E requires the first 5 fingers and pinched thumb and if you tried that it would be quite an effort and likely untidy. Try playing that D# 'mid 5' fingering and flipping the lowest finger off and on. Simple.

OK - probably too much info.