Update: Got my new RAM from Corsair today and... wow. I actually feel awful about how much trash I've been talking about the game out of frustration because it was running so poorly for me.
It's still not perfect because my rig is a bit on the older side, but it's perfectly serviceable now and exponentially smoother.
Just a touch miffed about the fact that the minimum recommended specs were really inaccurate in my case, but it's early access and there's a long way to go, I suppose.
I'm sure that further optimization will smooth things out even more as we go along.
So here's a general apology to anyone that I've irritated with my negativity over the last few months.
I also want to thank Blackheifer and Vometia for their input on this post, Blackheifer in particular for putting in the time to talk me through the entire process and find a solution that's perfect for me.