Blaster Master updated edition (same levels/weapons/bosses/layout except with revised graphics
A traditional Phantasy Star RPG
A Flashback (Genesis) sequel which stayed true to all its best elements (atmosphere, futuristic milieu, precise mechanics which had to be mastered etc.)
A Metal Gear game more akin to the original Metal Gear, which was more action- and task-based as opposed to story based, with a wealth of useful items and weapons; it really made you feel like you were all alone in the middle of a jungle with hostile enemies lurking about. No other MG game has featured that type of tense atmosphere imo, though they had an ambience of their own.
Another absolutely flawless Mario game (what little I played of Sunshine didn't impress me to nearly the same degree that Mario 64 did way back when). Barring that, a 2-d sequel to Yoshi's Island (SNES), which was packed the most originality (in mechanics, visuals, you name it) of any platformer ever, 'til this day.
A 2-d Castlevania game which retained that atmosphere and inventory options of C2: Simon's Quest while still maintaining the awesome mechanics of C4 and branching paths/characters/abilities of C3.