Just as a heads up, braids do lengthen the drying period. But if your hair takes a long time to dry, it takes a long time to dry. My hair (from full saturation) takes about... 6 to 8 hours to dry? I have medium/low porosity hair for the most part, so I can sympathize with you. Even after plopping, I usually have to wait an additional 4-ish hours, and that is extended based on the dew point and products I use...
But yes, generally, drying time does correlate to both hair porosity (and possible damage), and product use. If you want to cut down on dry time, I say invest in a diffuser attachment for your hair dryer; that's 8 bucks (or less) for a huge reduction in drying time. While others may diffuse to dry their hair, because my hair is so dense and takes so long to dry, I really only have the time to diffuse it to dampness, which is still a whole lot better than wetness.
As far as protein is concerned, you hit the nail on the head. Experiment. There are several lines that are extremely protein heavy, but I'd really just inch it up at a time. Start with something cheap, like Suave Naturals Coconut, which is a pretty light protein condish, and test your hair with the stretch test
. (Ignore their product recommendations). If you need more protein, shift to a more protein based line, such as CJ, AO, or whatever knockoffs you can find (though Curly Junkie and Aubrey Organics are on the cheaper side).
Really, I wouldn't invest in any major products to "try out" the protein, but keep a general hair diary, even just in your mind, so as you surf the forums you can find people with hair kind of similar to yours. That's basically what I did, and it's been working out, to an extent. Also, be aware of other products that curlies have sensitivities to, such as magnesium sulfate or glycerin.
The biggest part to protein, besides making sure you have enough, but not too much (which will make your hair feel like straw), is balancing the amount of protein with the amount of moisture.
Oh yes, and the first thing you mentioned---frizz. Well, for a lot of people, that just comes with the territory. I don't think I'll ever have a frizzless head by the end of the day, and I'm okay with that. But I am curious, what is your routine? You said you use Deva products, but some description might be helpful in assisting those who are trying to help you.
This may sound like a long process, and it kind of is, and kind of isn't. Everyone's hair journey is different, and I hope you have a good time on yours.