I have seen excellent things of pressure cookers. But they also cost money... Though the post you linked has more kitchen wares than I currently own (i.e. knives and pots), I'll stash it into my recipe box for a rainy day! Just one question - what is Manieschewitz? I have heard good things about mulled wine, didn't realize it was something made.
At least one good knife is a must. I have about ten and usually just use the ten inch chefs knife. It is the difference between chopping down a tree with a sharp axe as opposed to a dull sledgehammer. Makes things much more enjoyable and much quicker. Wusthof or Henkels are good and can be picked up cheap on eBay. As far as pots, I have some super expensive copper pots and pans that are absolutely amazing. My most used cooking vessel though is a cast iron skillet that I found covered in rust in my grandmother's barn. Cast iron is really cheap, lasts forever and is awesome to cook with. eBay is not too good for them though.
As I said, anything that can be made in a pressure cooker can be made in a slow cooker. The opposite is not true - chicken en mole in a pressure cooker is a disaster. I slow-cooked my carne until I got the pressure cooker. Knives and pots are cheap. Particularly if you aren't picky, and particularly if you buy them second-hand. I bought 3 Wusthof and a pair of scissors just a couple years ago for my mother-in-law and I think I spent ~$120. That's for good knives. Cheap shitty knives are practically free. https://en.wikipedia.org/wiki/Kosher_wine It's basically a redneck approach to gluhwein.
We not only thought that was the only Manischewitz, but we believed it was the only wine. One year, my brother brought an alternate wine to Passover and it seemed like a sacrilege. Now there's 10 different bottles of 10 different wines...but my mother still drinks only Manischewitz.what is Manischewitz?
Loganberry? Blackberry? Ontario has a very limited buy list - and I have never seen those exotic Manischewitzes here. The grape wine is only about $6 a bottle though and awful, of course. But we never knew. Shabbat and Passover involved only grape Manischewitz.
The others are just as cheap and almost as terrible. The whole point is to heat them up and add spices to them, since most mulled wine involves a crapton of sugar anyway, you're saving a step. My wife, back when we were just friends, made amazing mulled wine. Me and a subsequent string of girlfriends attempted to duplicate it (we'd fallen out of touch by edict of a particularly nasty ex) but failed miserably; I dated one girl who tried merlot. Mulled wine at Christmas was one of the truly great things about getting back in touch, and now we've been married like six years.