THOUGHTS ON GUITAR SIZES
The player is the music, not the instrument.
Tonally, any guitar body size can work perfectly for any music style or genre.
Guitar size only becomes a concern if you are playing live acoustically, with no amplification with loud instruments (banjo, violin, trumpets, bagpipes etc).
Typically, the larger the body, the more projection, bass, complexity, & general volume it has. However, have these four things ever been a concern to you when seeing a live band with modern pickups, & EQ? Guitar size is simply a non issue in almost all live band situations, with an intimate traditional acoustic setting being the outlier. While my smallest parlor is loud, if you play, say, in a traditional bluegrass band without amplification, a larger sized guitar is probably better.
For solo guitar performances & recording, a larger guitar (such as a OO 12 fret) can offer more tonal complexity.
Fingerstyle guitar need not be limited to an OM: Bert Jansch, John Renbourn, & Michael Hedges played it on a Dreadnought, & Duck Baker a classical.
Bluegrass does not only emanate from dreadnought guitars: Normal Blake’s 00 12 fret.
Jazz need not be played on an archtop guitar: Julian Lage plays a Telecaster.
Country isn’t only played on Telecasters: Willie Nelson plays it on a classical, & Chris Stapleton a Jazzmaster.
Blues can be played on more just 1920’s to 1930’s small bodied guitar sizes.
Be yourself, like all the musical giants were.
(Wanting to emulate the sound of original recordings is a separate issue.)
I recommend finding a body size/shape that suits your stature. If you have shoulder issues, a smaller body is best.
If you’re mostly only playing cowboy chords on the first half of the fretboard, I recommend considering a 12 fret to the body guitar.
Again, Any guitar body size works perfectly, tonally speaking, for any music style or genre.