in your case if we were doing that job it would be a dip.the reason why is everything was burned to a crisp also between the panels and is now rusting. you couldn't blast the areas that would need to be addressed. all the rubber and plastic has to be removed and replaced so your doing that anyways.
blasting the inside of a car isn't the best idea to do . the media gets into everything and is total hell to clean.
there is NO 1 best way to strip a cars finish. they all have good and bad about them.
it's common for a car that is dipped and e coats to still end up with debris to be left in places between the panels. like in the drawing of the rocker but this is the case also with all areas of the car like say roof structor. the down side is some areas do not have drainage to let the debris exit from and even with drainage debris still can be trapped and just be e coated back over.