Interesting points.
To Flaw 2, i'd actually say not neccassarily, if Mahoney shoots off his line and stops a runners forward momentum but the runner carries on sideways and the next guy over actually finishes the tackle, that missed tackle has still contributed to effective team defence and that lower post miss number. Even if he gets flat out bumped, like most hookers he gets spotted up, but if his line speed means he's bumped going in hard and low meeting ball carrier at the ad line rather than catching on ball sitting on his heels and getting carried another 5, which is more effective?
The other flaw with that flaw is did his misses actually open more space outside? Or is he defending in the middle and Ciraldo wants two shoulders into every ball carrier so his middles are in tight anyway so he can rush off the line like he does confident to put his body in front and not to worried about being bumped becasue the system has the middles there in tight by design?
As to flaw 3, I'd also say not neccassarily, an outside back on a bad team might have to cover more space because their middle gets shortened up more routinely than a "great defender" on a good team. The space between the 4 defender and the sideline might be wider on a shitty team than a good team because the middle is useless, which is always going to effect your tackle percentage and perception as a defender becauss of the extra space you have to cover and less time you have to make decisions.
Most of us would have played on good and bad league teams at whatever level during our lives, and from my own experience as a centre, defending on a good team vs defending on a shit team are two completely different assignments. Nothing changed in my ability, but my edge leaked way more when I had lower quality players inside me.