Heya,
Nice, I like the first one best for overall feel (expression seems more earnest and casual, which matches the acoustic and flannel more to me). Lighting wise, I think dropping ambient light more would have been nicer, and using the bounce flash as minor fill from a source a bit more to the right perhaps. The lower back ambient would have given a bit more pop to the subject. Example, drop ISO to 100 (or even 50), increase SS to 1/200s and ambient would have been over 1 stop lower, even up to 2 and 1/3rd lower if you really wanted to make it significantly different, worth exploring. Flash in manual with whatever power level needed to get a nice soft fill on the subject.
Very best,