I'd go through the stack of tops and divide them by a) absolutely needs to be long armed, b) nice to long arm, c) I could quilt in a pinch. Then I'd save up for the long arming and tackle the ones I could do in a pinch. I'd use my walking foot and either do a grid or stitch in the ditch. As I got better, I might find I could maneuver my machine a little easier and get a little fancier. But I allow my quilts to NOT be perfect. At least they are finished, and I can give them away, sleep under them, or even use them as tablecloths or picnic blankets.
I have found that free motion quilting is too stressful for me. I worry about it constantly so I have stopped doing it. I do quilt bigger quilts in sections and sometimes I do some free motion in those. But mostly, I just use my walking foot, and I'm getting better at it all the time. I recommend Leah Day's book on walking foot quilting. It really helped build my confidence.