I've got shorts from all price ranges. I will have to say my favorites are my more expensive ones (the $80 shorts versus the $40 shorts) with the thinner chamois. But I think it's more personal preference than anything else. I find thicker chamois make my legs numb on long rides from the pressure, so I mostly buy tri shorts now. I think the biggest thing to know about shorts to prevent chaffing and irritation is to always wear a clean pair (one use only per pair before washing) and take them off as soon as you are done riding.
For chamois cream... I really like using it. I use the Hoo-Ha Ride Glide and find that it really helps keep my skin protected. I thought the same as you that it would cause everything to get all stuffy in there and with the sweat and everything, but actually I didn't notice that at all. What I did notice is that my skin doesn't get irritated and raw and the tea tree oil smell it has helps cover up the sweaty gross smell.