When I got my Bernina sewing machine and could achieve small stitches that way, I started to increase the size of my hand stitching for decorative purposes, using cotton perle and silk buttonhole thread. In the late 90's it was about 5 stitches per inch in 'City Girl Dream of the Sea' (below)
And 5 years ago in 'Serifos Storm'(below) I'd increased (or should that be decreased!) to about 3 or 4 stitches per inch
As part of the TIF challenge last year , I returned to using glazed quilting thread but in huge tacking stitches (1 per inch! ) - appropriate to a piece about barely being held together. Although, with practice, I could probably achieve very fine stitching again ,my preference now is for combination of machine quilting and BIG handstitching which feels right for the scale I'm working now ( ignore the quilt police!) I use chenille needles ( needed to penetrate layers of acrylic paint as well as fabric and cotton wadding). The key it seems to me is evenness and consistency and developing a rhythm that suits and is enjoyable.