Generation I:
+I um... don't know. They were the originals, I guess?
+Great OST
-While holding up a lot better than other Gameboy games, these games aged extremely poorly (imagine what could be said about other GB games, then? Don't get me started)
-Lacked ability to play as a girl, even though a girl trainer did exist in artwork.
Generation II:
+Built upon R/B/Y in a beautiful way that was so much fun and nostalgic for me as a kid.
+Crystal finally added the option to play as a girl.
+Fantastic OST
+While not the generation with the most of my favorite Pokemon, it certainly beats other generations in it was pretty solid with the fewest I think are bad.
-Is dated in many of the same ways as Gen I.
Generation III:
+Made many QoL improvements that keep the games from feeling anywhere near as dated as their predecessors.
+Great OST, again.
+Began the trend of remakes.
-Took steps back from G/S/C. Such as the removal of the day/night/time system.
-No continuity from the previous two generations.
-Some bad Pokemon designs, but hey it happens in all generations.
Generation IV:
+Brought back the day/night/time system.
+Snow for the first time (but why in the world do they count it as hail during battle?)
-Extremely forgettable OST.
-Some of the worst designs in all of Pokemon. Most of the cross-gen evolutions were abominable.
(I don't remember Generation IV very well. I played Diamond in 2008, and that was it)
Generation V:
+Hit the reset button much better than Generation III, with making us only use new Pokemon before the post-game. Made things feel very fresh.
+Some of my top favorite Pokemon came from those generation. Not every Pokemon was a winner, but there were a lot of fantastic designs.
+Seeing a non-Japan based region for the first time was neat.
-Mostly forgettable OST again (not as bad as Gen IV, though)
Generation VI:
+Incredible OST, my favorite!
+Kalos is a beautiful region (aside from being watered down by being 2.5D) based on an exciting location and full of variety.
+Pretty strong generation for Pokemon designs.
+3D Pokemon designs are great, much better than the Stadium ones we were plagued with for an eternity.
+Trainer customization became a thing, and is amazing!
-Region still being 2.5D was very disappointing.
-Gen I pandering started creeping on us in these games.
-Extremely short generation that they cut off far too soon.
Generation VII:
+Moved further away from 2.5D, were much more 3D.
+Brought regional variants... even if all of them were Gen I. *sigh*
-Soooo much Gen I pandering. Make it stop!
-Inconsistent difficulty.
-The cutting of the National Dex (not the cutting of Pokemon that happened in Sword/Shield just the cutting of the Dex)
-Some of the worst Pokemon designs ever (especially the Ultra Beasts).
-While being 3D, the games felt even more limited. The lack of a movable camera doesn't help.
-Unexciting region idea, IMO.
-Mostly forgettable OST.
-LGP/E became a thing. That should have never happened.
Generation VIII:
+Regional variants expanded beyond Gen I, even though a lot of Gen I ones still happened.
+Galarian Rapidash! <333
+Neat region concept like Kalos, and felt even more like the land it was based off of than any game previous.
+Wild Area - far from perfect, but a nice effort.
+Zacian and Zamazenta are best legendaries.
+The gym concept is great.
-The big Pokemon cut.
-Forced Exp All
-While Wild Area is a fantastic idea, it's not balanced very well and with the forced Exp All, you are punished for wanting to spend time playing in the Wild Area, as Pokemon quickly become overleveled.
-Story has a great structure, but underdeveloped characters and the plot being sprung on us at the very end of the game sadly messes things up.
-Very minor, but boy do the graphics in Wild Area really suck. Calling the trees OOT trees is no exaggeration at all.