Skills are no problem at all. What else are you going to do with money other than respec your character to try out all the different skills?

Stats are another matter. I think I've hosed my first character, a ~35th ranger. I've put too many points into DEX, and only enough into the other stats to use items I find. Not many things but spiders and bosses close, but with only a little over 200 HP, I get one-shotted a couple times per game anymore.

Anything I can do about it now other than gulping stat potions when I see, say, Snake?

As a corollary, if this character isn't salvageable, how do you recommend splitting up stat points on a new ranger?

Thanks. Sorry I forgot to mark this as a question.

That makes Demon War worth it all on its own. Potion chugging is fine, but it looks like I can only have two active at a time. I can have a plethora of bad ones, curse, burning, poisoned, caltrops, weak, etc, but only two good ones. I'm not sure what the rule is, yet. Maybe it's one resistance and one stat? When I tried to swig a lightning resist and a poison resist, it gets rid of the first one.

Yep, one stat buff and one resistance buff (and the game counts the potion that increases your find chance as a stat buff, too). And if you save and quit with a buff/buffs active, it/they won't be saved -- so unless you're absolutely swimming in potions, don't drink them (at least, not any of the better ones) unless you're sure you're gonna be playing for another 15 minutes (or close to it, at least).

Regarding Demon War: it does add a lot of cool features, but there's also some annoying crap, too. You'll be pestered a lot more by townsfolk, who might begin to starve to death without you constantly giving them money, for example, or start getting into fights with one another (and they CAN kill one another). You also gain the ability to equip them all with certain basic armor items, but that can also suck up a fair bit of time that would better be spent resolving quests.
All in all, it seems the expansion makes the game noticeably tougher (at least, I've noticed that my number of towns lost has grown disproportionately since I installed it). But maybe it's also related to the methodical, "clear each floor before moving on to the next" way I like to play -- you really have to act swiftly, and be able to effectively prioritize the more pressing quests to be very effective. Helpfully, though, the expansion does also offer additional ways to customize the challenge level of a new town, including specifying the (rough) size of the dungeon. :)
EDIT: Here's a post I made with some info on the town creation options that are available with <i>Demon War</i> installed.