Otter15, the best thing for dry, itchy skin is to apply Doublebase Gel after your bath or shower. You can also use Doublebase Emollient Wash Gel instead of your usual soap or shower gel. I find the Doublebase products are also non slippy, so no fear of going base over tip as you get out of the bath, which I am afraid you might do with oil in the water. It is best to avoid soap, shower gel, or anything else with SLS in it as these are very drying to the skin.
As to the VA, showers are best as you can avoid getting water between the labia. This washes out the friendly bacteria and upsets the ecology of the area. Good luck with keeping it all under control!
JP x