Passage making preparation

[Almost-There]

I'm looking for a new boat and I keep coming back to a 39 Allied that needs work. Now I'm no stranger to the ordeal and have been in the marine industry and done several refits in the past. The issue is I'm unsure of where to concentrate my efforts for offshore work with the rig.
If I get the boat my current plan is to drop and inspect the keel,rudder and chances are I'll replace all the through hulls. But beyond that I'm unsure of where to concentrate my efforts especially while she's on the hard.

Is it advisable to go overkill on things such as chain plates etc? Machining and fabrication isn't a problem and neither is glasswork. Would it be advisable to just go a head and replace/beef up all the hardware backing plates?

As it sits a repower is without question as would be all new tanks. But I'd like to get everything that has to be done on the hard out of the way first in order to get some time on the water and go from there.

What's is everyone's opinion on a sea chest vs multiple through hulls? If you could've would you have gone with one? Or is it overkill.

Thanks