"You could try something like wins"
smh...
I understand your point that, for a coach to receive your praises, he needs to pile up wins. You're not going to find a lot of dissenters to that opinion. But the discussion has been solely about how to measure the value of a team's offensive schemes, and you're completely missing the boat here. Strictly speaking, a "good" offensive scheme is one that gets you the most good shots. Circling back to that Houston Rockets thing I was talking about earlier, Daryl Morey has said his analysts chart out all the shots and give them binary "good/bad" ratings. By their estimation, NBA teams are getting "good" shots at something like a 55% or 60% clip. Thus, if Morey's own team is getting them at an above-average clip, he's pleased with the offensive schemes. Notice that the actual offensive output doesn't factor at all into this assessment; the exercise is to strip player talent out from the equation and try to measure exactly what gains a coach's offensive scheme is giving you.
That's why I said we just don't have any good statistics to measure this stuff, to which you toolishly responded, "wins." There are bad teams that run good offenses, and there are good teams that run terrible offenses. Separating out when player talent is masking a coach's deficiencies or exacerbating them is the problem, and you have given no solution.