Happy to help! I'm curious how your hair is without product in it - is it dry on its own? I stopped dyeing/heating mine when I grew it out from a pixie, so it is relatively undamaged (other than being super-fine) and holds moisture really well. Back when I abused it more, it was the opposite: couldn't get moisture INTO it. I think low porosity has a lot to do with this.
So if your hair seems dry/frizzy without product, maybe try some DTs to really moisturize it - that way the products you put on are holding something in, instead of keeping moisture out. Same concept as using oil to seal hair, but I find oils way too heavy to my hair. I use coconut oil as a DT overnight once a week, and I'm trying mixing in some other oils next week (Castor oil, and Badger's Seabuckthorn oil blend). I'm still learning up on the whole dewpoint thing; I live in a part of Northern California where it varies very little, so I haven't had to think about it a lot!
I read in some other posts in this thread that you've had good luck with mousses. Me too. They seem friendly to fine hair (although a bad mousse is REALLY bad). I like Peter Lamas, which comes in a pump instead of having propellants that can damage hair. It's CG friendly as far as I know...
Also, I just added Garnier Pure and Clean Gel to my routine yesterday, as my "last coat," and after I gently SOTC it looks great. Maybe try it! I've had bad luck with other Garnier products, but I heard some good things from people with similar hair.
A thought on using a whole product line: one line tends to have similar ingredients, and if us fine gals are supposed to avoid product build-up, that might be another reason to mix lines. Similar ingredients in several products = faster build up? I don't know. It makes sense to me. Anyone else have thoughts on that?
If you feel like it, maybe we can get a picture of your hair, so we can see what it's up to that you don't like? Maybe you are indeed being overly critical! But I know the feeling, when product after product sucks for you. I try to only buy from places that have good return policies, and keep those receipts! It adds up.