>>24591571They are.
Platinum has a super comfy region and probably the highest difficulty (though it's still easy since it's Pokémon). Avoid Diamond and Pearl like the plague, they have major issues that Platinum fixed, make sure you play Platinum if you want to play a Sinnoh game. HGSS are fantastic remakes of Gen 2, and probably the best starting point if you just want to play another Pokémon game since it'd be familiar.
BW1 are polarizing because you can't catch any old Pokémon until postgame but I really like it. BW2 have more variety and a fantastic place in the game where
you get to battle literally every Gym Leader and Champion up to that point but it suffers a bit from handholding. It also has a challenge mode, but you need to beat the game or use an Action Replay to unlock it.
XY are lame, there's way too much handholding and they filed down the difficulty even more than usual so the only reason to play it would be story. And Game Freak sucks at story.
ORAS I don't recommend either. They're near-1:1 remakes of Ruby and Sapphire (with a couple things removed like the Game Corner and, frustratingly, the Safari Zone) but don't have any Emerald content. I'd only suggest playing it if you REALLY love Hoenn and want to see it in 3D even without the content that makes Emerald a better game.
tl;dr I'd try out Gen 4 and 5. Gen 6 I'd wait, the third version for XY might fix the issues with those games so you should just wait until then.
Also try out the Pokémon Mystery Dungeon games, they're great spinoffs if you like dungeon crawling.
