6 stitches per inch is great for a beginner, stop worrying and just concentrate on keeping them even and not messing it up when you get to a seam allowance. My stitches were that size for a good year or so after I began quilting, and they're only 8-9 per inch now - which I think is quite small enough!
The main thing is that you're comfortable and that the stitches are even. The quilt should be well basted, and then it's a matter of finding a position that's comfortable and getting the tension right for you. Some people like it drum-taut, some people like no frame/hoop at all, and most are somewhere in the middle, so experiment.