I get your points TC but a couple of points.
However, the figures about tackle count are available on a couple of sites, most notably super coach, where you'll find Schuster's rating was consistently higher that Forans last year (Manly's highest two were Turbo and DCE). That's based on the amount of work he is doing on the field.
Suggesting he may pace himself in respect of tackling, may be valid, but then if he is both required consistently in attack and defense and is one of the few 80 minute forwards that would make sense wouldt it? And it doesnt get past the fact that he did have a high tackle count and as a second rower he is more often facing heavier traffic in the middle of the ruck facing opposition forwards, than what is faced out in the backs. The only back in the Manly side who has a high tackle count consistently is DCE.
Sharpness and involvement come with energy available. And I recall Schuster in attack often playing outside Foran last year in attack (he played closer in defense) and he did a lot of follow up running especially when Turbo was making one of his many breaks (or didnt you notice that).
Last year he was heavily involved in both attack and defense, though by far the two most brilliant in attack were Turbo and DCE (supported by the stats). Problem is its so easy to forget yesterday and be caught up in the here and now. I recall similar arguments about Walker. His first year or two at Manly were quite brilliant, but injury and court matters damaged his image ad suddenly many were suggesting he was a wasted salary component. He gets his act together and succeeds in his new role and suddenly he's the great asset we dont want to lose. Such is the fickleness of football supporters.
A fit Schuster, as long as he gets his head together, is a potential top star of the game and all of those question marks you've posed I suspect will be answered with extras...as long as he gets his head together as I said. I look forward to discussing this again late next year.