See the results of this poll: Which spelling do you like best for "FAY-ruh"? MN is Belle.
Respondents: 34 (This poll is closed)
- Feyra : 18 (45%)
- Fayra : 18 (45%)
- Feyre : 3 (8%)
- Fayre: 1 (3%)
To avoid the inevitable mispronunciation of “Fair” I would choose one of the versions ending in A. I think Fayra looks the nicest in that case.
Definitely Fayra. You won’t get “fair” but it also wouldn’t be confused with “[name_f]Freya[/name_f]”.
Fayra had a beautiful sound, look and meaning! 
I think this spelling is the nicest and most intuitive.
I personally prefer the look of Feyra, but because of the popularity of [name_f]Freya[/name_f], I would go with the Fayra spelling since it makes the name more distinct!