Alright, I've gotta ask here in case Evan sees it: have the spawn rates changed recently? I ask because there's quite a few of us over on the reddit subs who think the spawn rates have increased significantly. For instance, I am not surprised at all when I cross a floor I've already cleared and I encounter an enemy on the way. I am surprised when doing the same and I suddenly encounter 3 or 4 enemies close together, and as I start to back up so I can handle them one at a time another one comes up behind me.
A lot of people have commented on this over on reddit, and my personal experience is that I'm much more frequently finding myself frustrated by encountering _yet another _ bad guy right after having just handled several. It's starting to feel a bit out of hand (and I say this as someone who's played for a couple years and has a fair amount of experience at this point).
If it's not the spawn rate, is it possible that the new-ish floor designs (which allow for rooms to connect to each other without walls between them and such) might actually be leading to higher densities of enemies in some places?