I know you're of the opinion that everyone sucks at everything, but I disagree. I believe Tabor and Lawson can both be good CBs seeing as they both showed they were able to do just that this year without a pass rush. Get them that and they could be great.
Diggs showed exceptional play making ability at safety in limited time there. Why wouldn't we want him to keep it up? There's also Killebrew in development, who has shown flashes. I wouldn't hate a developmental guy at FS for Glover to mentor, but it's not even close to the top of my priorities.
Getting back to the thread topic. I think perhaps the move that will have the biggest impact has already happened. Replacing offensive line coach Ron Price with Jeff Davidson might actually get the Oline to produce some running lanes and hold up in pass protection. I think we need either a RG or C as Glasgow can play either, but I think we're set at the other starting positions as long as we're healthier than last year. We could use an upgrade at running back, but good run blocking can make average RBs seem good and with JBC and Stafford we don't need an elite running game. Just one good enough to keep defenses honest and churn some clock when we need it to.