I think the whole issue is that it has become too easy to hit the spot each time with whatever bowler whereas in fact it is the hardest thing to do; thats why bowlers succeed or fail in a spell; the either hit the right length or they dont. With the bowling mechanics as they are there is too little error room. I would like to see us return to the previous mechanic in that point of release determines length as in real life....
I suppose they could *possibly* program it in so that the 'Ideal' green bar changes based on the bowling modifier/length chosen so as not to affect the core bowling gameplay from what it already is, then it would work. To replace the length selection completely would be too radical a change.
E.g.
I choose a yorker, an early release would mean a full toss, a late release would be a half volley. Select a good length, early release = half volley, late release = bouncer. The varying degrees of timing would then affect the distance between the selected length and the affected length.
This way, you get variability of length, but also maintain the bulk of the current bowling mechanics...