It is questionable whether tapered vs. roller is of real benefit in the steering head if they are properly greased and torqued, but many opt for tapered. I would go straight rate vs. a progressive rate front spring, but new springs will give you bang for the buck. The weakness is the lack of damping adjustments, which you can tweak to some degree with fork oil weight and amount, or Gold Valves or such (don't know if GP Suspension in Oregon has anything for the ST). As for wheel bearings, if you replace them, I would repack before installation to ensure there is enough grease (normally manufacturers say they fill 30%, but why not 50% with a good quality #2 (#1 too runny) grease, or moly or titanium dioxide grease).
