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Radical Red is so poorly designed, it's disgusting. You're forced into using the most optimal Pokemon available to you with very little wiggle room, or you're getting swept by the gym leaders. Speaking of, the gym leaders are the only ones with any level of competency in their teams. The normal trainers are fucking pitiful, always low level and not providing any sort of challenge with very little return on your battles (low EXP gain as a result), almost as if they're forcing you to be underleveled for the inevitable "boss" fights.
Inclement Emerald does what RR wanted to do but way better. There are a multitude of options at the start that let you tweak the difficulty to your taste, a large Pokemon variety available to you even before the first gym (without the tedium of Dexnav on top of that), and a proper difficulty curve. It also doesn't enforce shitty Smogon rules.
Only thing RR has over it is Gen 8 Pokemon. You could make an argument for RR's "Casual Mode" too (nullifies EVs/IVs).
It's a real shame though, because I like the Kanto region better than the Hoenn region.