Level design is not the problem
Sonic Adventure has Aged extremly well: SEGA just makes poor ports of the Dreamcast original
Ocarina Of Time has aged very well. I could play that game a billion more times, compared to SA1.
The GUN truck........basically SA2, version of the Whale. I mean yeah that was nice.
The problem is originalism with respect to the original fan base. Meaning the game has to be unique, replayable, and enjoyable like the fun game, without over doing it. Reason why SG is nice, is because of the designs, and that memories that accompany the gameplay.....uptil the time boss.
I wish SEGA could just bring back ground, scratch, Sally, and even the stupid characters from other toons, as well as the videogame world. Even so, they will not even be able to execute it. Some Sonic fans are thinking in terms of the videogames, other Sonic fans are thinking about the comics, and the noobie fans, are thinking in terms of the GBA games. It is just so silly, because this could go on forever.
In another ten or twenty years, SEGA will release, SONIC GENERATIONS II, and will have all the stuff we found wrong, being released as greatness.
Yeah SONIC, made lots of money for SEGA as with Mario did for Nintendo. It was great times, I will admit, and I could and would rather go to my game system, and play some Sonic right now, I mean it. I could play the original games, including the auwsome extra long Sega CD game. I could play the SEGA Dreamcast SA1 a couple of times, and Shadow is great.