Super Mario 3D World > Super Mario 3D Land
Resident Evil 2 > Resident Evil
Smash Bros. Melee > Smash Bros.
Mass Effect 2 > Mass Effect
TES: Skyrim > TES: Oblivion

Super Smash Bros Melee

Assassin's Creed II

Most sequels I like more than the originals are better to a point. Skyrim had numerous improvements but the removal of classes and proper attributes was a let down. Xenoblade Chronicles X has a better structure to its world, better side content, and improved gameplay mechanics in many areas but the main story isn't as consistent.

Also, I haven't played the Kirby that came right before Super Star but based on what I've seen, it was a big step forward.

Uncharted 2 was the only one that came to mind immediately, but I agree with the mentions about Metal Gear Solid 2 and Assassin's Creed II. MGS2 improved a lot of what was already great in the first game, and Assassin's Creed II fixed a lot of what was wrong with the first one, as well as improve the things that were good.

As for Uncharted 2, it was largely more of the same, but this time with a lot more variety and a multiplayer component. However, in my opinion it's the variety that really made it that much better.

Back in the day, Driver 2 was also great and in my opinion improve a lot compared to the first game. Again, more variety, but some neat features too. More different cars to drive, environments that played differently (e.g. curved roads), and the ability to walk (it was rather clumsy but it allowed changing the vehicle during missions).

I reckon Total War series has some pretty drastic improvements too. I haven't played them all so I can't comment a lot, but it's really come a long way and I suspect there must have been a jump between some of the early games.

Pokemon Gold/Silver, Assassin's Creed II, Super Smash Bros. Melee, Paper Mario: The Thousand Year Door, and Fire Emblem: Radiant Dawn

Coming directly from the previous game, not necessarily the franchise as a whole:

Age of Empires II
Mario Kart 8
Suikoden II
Witcher III
Pokemon Silver/Gold
Uncharted 2 and 4
Megaman X
Mass Effect 2
Skyrim

I dunno, I guess there are many more worth mentioning.

Smash Bros Melee
Pokemon gold/silver
Terminator 2(Know it isn't a game but whatever)



I know for sure Pokken 2/Splatoon 2 will be a massive improvement, as it's obvious they both are well received by the gaming community(and casuals)

I have a strong history with the #2 in a series lol
Mega Man 2
Sly 2: Band of Thieves
Uncharted 2
Sonic 2
Thief II
Red Dead Redemption
Silent Hill 2
Assassin's Creed II
Paper Mario: The Thousand Year Door

Uncharted 4. Really, it's 2 or 3 steps above UE3 in every conceivable way... and it's a big jump. The gap from 3-4 is bigger than 1-2 imo...

Dead Space 2

SMB3.

It pretty much redefined the 2D platformer and had a combination of variety and polish that's still largely unmatched in its genre and its successors.