hard stator support, hard sun shell, check that drum for straightness and cracks, probably a upgrade to the 2nd servo even if it is just to a "694" or even a "692" but i like a sonnax if you can fit it in the budget.
I like a Cadillac AA unit for the vb and governor with some mods if you don't have one of the fancy vb but the brf, cz and others can be less of a challenge.
tight setup on the direct clutch pack and attention to detail on the clearances in the unit is very important for longevity