I don't want to have to pin a pattern on fabric to cut straight line pieces when I can simply cut (2) pieces 15" x 19". However, I don't like getting pathetic directions either. That happened with the twister wreath pattern and I was really disappointed.
Lazy Girl design bag patterns have full color step by step photographs of the pattern, with well written directions, but no pattern pieces because they are easily cut with a rotary cutter and ruler. Her patterns rock! (no affiliation). Try one of them before you write off all bag pattern makers, some of them are very talented. JMHO