I feel looking into individual outcomes of single deliveries, or the bowling figures within a single game, or even a set of games, is missing the forest for the trees. These things all balance out over large sample sizes. The variance is huge, and your players aren't ever going to repeat the same performance week in week out. This is especially noticeable in International cricket, where each player can only really manage 20-30 games over a career at best. Very possible for them to end up with crap career numbers even tho they've mostly bowled well, a combination of poor luck/being forced into difficult roles.
Just to be clear 'quality' here is the number they show in the commentary that you can read off at the end of the game. But it appears that is more to do with the line and length of the bowler than the other skill metrics. Whereas the overall combined 'high skill' of the bowler and thus overall attack is more important when taking wickets.
I don't think L&L is that big a factor in determining BQ. Frans Potgieter is a good example - very accurate, but very little quality behind the ball, so he just kept bowling crap but in a good area. Some lower accuracy bowlers are incredibly potent because their 'best ball' is very very good. I think all 3 skills are equally important, same goes for batting, and so you want players to be solid in 2 out of 3 areas. Then comes the trick of balancing them all out, and using them at the right times.
So many more factors affect BQ as well - conditions, touch, the stage of the innings they're bowling in. Sometimes the RNG just doesn't go your way either, and everything can be optimized and they still bowl crap.
The flip side of course is that somedays everything goes your way, and your 2-over-a-game part-timer can end up taking 3 wickets in 5 balls to help you beat India
