Oh, numbers:

Planter: 4.5"dia. x 3.5" h

Longest Petiole: approx. 15" (it's the one coming forward in the picture)

So the leaf longest leaf now leans the other way (towards window). This pulls the smaller piece upright, but pulls the base of the plant up a bit (see pictures) Are these just mounting type roots that don't care about lifting? Do I actually need to push them back down? The leaf that was towards the window is pretty upright.

No drainage does seem like a watering nightmare, and your way of putting the draining pot inside the decorative pot is better, assuming you're letting it drain after sink-watering.

You could cut off the big stalks if you don't want to stake them. Then it'd be cute and proportional to the pot.

I don't know when it will outgrow the pot, but I do know that I've been harshly top-pruning my monstera for years now without ever root-pruning or doing anything at all to the pot and media. No rocks in or on the pot. I inherited the plant and have certainly not babied it. It seems tough and vigorous providing it gets sane watering and good houseplant light.

If you don't top-prune and the plant is happy then it will want to become gigantic. This is how I've seen them staked https://duckduckgo.com/?q=monstera+pole&t=h_&iar=images&iax=images&ia=images So it's really up to you if you want a big jungle beast or a cute little guy in the small pot. You can still get the nice leaves with just a pot and not a pole.

You need drainage! Re-pot that into a bigger pot and put a stake it, if you want it to climb and grow tall. You have new growth coming from the tall stems also, so don't be surprised if those big leaves don't make it. It looks like the big leaves could be divided off for two plants, but I don't think you're ready for that. Monsteras like to be drenched when they are really dry, and not consistently moist on top. So please, above all else, use a well draining soil mixture and put in a pot with holes on the bottom.

I don't know how much I care if it gets tall. I do want fenestrations. I'd be happy to find it a stake, but is there a best style?

I hadn't really thought about pruning the floppy leaf off ... it's clearly had a leaf pruned off before, but I figured that was to make it fit in the box it came in. If I prune it, does it need to settle in first, or is there a best season for pruning a monstera?

I don't need two of these ... I have space for one, so division isn't really in the cards unless it's for plant health, as I don't have anyone to give the extra to (if the plant needs it at some point (like the dozen or so jades), I could try keeping them tiny, toss the spare divisions, or stick them out by the street labeled free or something - a lot of trouble if pruning is just as good for the plant.)

I guess I should clarify, by soak I mean let it sit in water for x minutes and then drain and put back vs run water through and then let drain and put back. African violets in our house get water run through them (they live next to the sink, so it's convenient); the orchid gets set in a cup of water for 10 minutes; the rest get watered with a pitcher or similar. Pitcher wouldn't be practical for the current potting situation, as the planter isn't really the same as a saucer, though I suppose could function as one slightly. In order to survive in this house, plants must pass the desert test, as while they'll usually get checked at least once a week, we're more likely to underwater than overwater.