As part of a major maintainance campaign at 120k miles, I need to prioritize choices. I am a slow DIYer. Any suggestions?

0) Hopefully the rough idle has been solved.

1) R&R the serpentine belt and pulleys (is this as bad a job as it sounds?) The belt has cracks on ribs every 1/16 inch and the engine sometimes clatters at idle. In the archives is a horror story of a bearing bracket which failed and trashed the system. Is it wise to replace just the idler pulleys or pulleys and brackets amd/or tensioner and shock? What about the fan clutch bearing bracket? What about the wa$$er pump? Is this a good time to have the alternator bearings replaced and commutator turned (the big bosch units on my BMWs went 200k).

2) Replace the original wiring harness which has hard but apparently intact insulation.

3) the 104 engine is leaking oil, probably from the front timing cover--the head gasket looks dry.

Should I do the front gasket with the poly belt now or wait until the head gasket fails? (and live with cardboard on the garage floor). Should I do the head and timing gaskets with the wiring harness? (seems the head could last several more years).

4) The driveline has small but noticeable play in the ujoint (maybe 1mm), and there is a crack in the rubber of the center bearing support. The front flex disk is undistorted but has very fine cracks that appear to be on a surficial layer that seemed to flake off when I scraped it.

5) dried gunk on the left side of the final drive and adjacent cv joint (not the boot)

6) Although aligned by the dealer, the steering still pulls a bit to the right and the Michelins XGT H4 pilots only lasted about 15 k miles (suddenly this seems very minor).

__________________
TomO
94 E320 Wagon, 170k, totalled in 2006
2002 BMW 525i Wagon, 75k
1991 BMW 318is (two of 'em)