I'll start
>Red/Blue
Fun in retrospective, kinda broken.
>Yellow
Cool idea on paper, not so great in execution. Otherwise same as Red/Blue.
>Gold/Silver
Great mechanically ruined by a shit level curve.
>Crystal
A decent version of Gold/Silver.
>Ruby/Sapphire
Great game all around.
>Fire Red/Leaf Green
KANTOOOOOOOOOO but actually playable.
>Emerald
Ruby and Sapphire but even better.
>Diamond/Pearl
Unoptimized trash
>Platinum
Everything wrong with Diamond/Pearl are no more, only way to play Sinnoh.
>Heart Gold/Soul Silver
Amazing remake that unfortunately still has the same problem as the original.
>Black/White
Interesting experiment and a fun one at that.
>Black 2/White 2
Works of God.
>X/Y
Best Multiplayer, worst Singleplayer.
>Omega Ruby/Alpha Sapphire
Great remake of Ruby/Sapphire but lacking compared to emerald.
>Sun/Moon
Underrated and surprisingly challenging entry, shitty start.
>Ultra Sun/Ultra Moon
Sun/Moon but without a reason to exist.
>Let's Go
Mechanically sound but souless and boring remake of Yellow.
Pic Related's my first Pokemon Game. Post yours.