There's no guarantee that your hair won't frizz in humid weather. My relax/texlaxed hair was so damaged/dry that it acted up
awfully in humid weather. Ironically, my naturally curly hair loves the humidity and rain. I used more products when my hair was relaxed, because it was low porosity and never stayed straight (relaxer didn't hold well), and it frizzed horribly.
But really,
it becomes really a game of experience. You still sound skeptical, so you can relax your hair if you really want to, but those against relaxing are just warning you of possible side-effects. Also, I definitely recommend having someone else doing it if you're doing a home relaxer...
And you definitely don't need that many products. While I think your hair looks awesome in the first pic, you're right in that for most, that amount of product is a little too much. I usually have 1-2 products in my hair at once, and it's my leave-in and a few drops of sealing oil. I kind of know what my hair likes now, so it's not really that difficult, nor is it a very time-consuming process. It's a matter of getting to know your hair.
But really, whatever you think will work. It was much cheaper/low maintenance for
me to go curly.
P.S. I'm a bit confused why you posted such a thing in a forum that is known to be a haven of natural curlies. It's kind of obvious that most of the advice that you'd get is to not relax your hair...