If you are restocking rather than shopping: buy the boring things first. Wash, shave cream and toy cleaner are the ones you only notice when they run out, and they are the cheapest things on this page.
If you are sensitive or prone to irritation: fragrance free, every time. It is the single change that resolves the most complaints across this entire page, and it costs nothing to try.
If you shave: cream and a sharp blade do more than anything applied afterward. Most razor bumps come from a dry shave or a dull blade rather than from shaving itself, so the fix is upstream of the soothing mist.
If you are building an actual routine: pick the two things you will keep doing. A short routine you finish beats a long one you abandon, and the pelvic floor work in particular only pays off on consistency.
On materials: non porous and unscented wherever there is a choice. Medical grade silicone, glass and steel can actually be cleaned. Fragrance is the most common cause of irritation in every aisle feeding this page.