Big rings the best
Although I'm not really sure what you mean by "more straightforward." Sonic 3 & Knuckles having a bunch of alternate paths to clear a level is one of the best things about it. And it's not like you can't just take a "straightforward" path in S3&K anyway.
Sonic 2 has plenty of alternate paths, too.
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Support Barret Wallace (Final Fantasy VII) for Character Battle IX!
http://img687.imageshack.us/img687/3834/banner1barret.jpg