I'm cheap when it comes to liquid as well. It's the sole reason I got into DIY. I pretty much gave up on trying tons of different liquids. I spend $20 per month on supplies and feel bad if I go over that. There are a few out there I have really liked, but I also have an apocalypse stash of full bottles that are over a year old. I've held onto them because I would vape them if I really, truly had to, but they are definitely getting old at this point.
Worst flavor is one I actually never even tried - I just went by smell. It was a tobacco and it smelled like rancid soy sauce. That's the only one that has gone down the sink. Another flavor that I hated, but many like, was a tobacco that tasted like graham crackers to me.
Every now and then I am tempted to try out a new flavor, but I stop myself 90% of the time. I made the mistake of putting just a few drops of my brother-in-law's all day vanilla vape in my carto filled with menthol the other day. I figured I would get a few minutes of a vanilla menthol. Those few drops of vanilla infiltrated my carto to the point that I am still tasting it 2 days later, but being cheap and frugal, I just keep refilling with menthol and using it.
I guess bakery flavors and a lot of tobacco's out there just aren't for me. People talk about some amazing cocoa-caramel-vanilla-ry4-tobacco, and I instinctively go "ewwwww." I want to eat my desserts, not vape them. It's a bridge I just can't seem to cross. Crazy fruity juice is fine, though. Just goes to show that taste is very, very subjective.