I couldn't point out every area of 3D design in a single post. I just wanted to make a few points, and tried to highlight some of the positives even if I have a relatively negative opinion on the 3D in Colours. Seeing as you mentioned it though, Starlight Carnival 5 (not 6) is weird; it has a full 3D section at the end but also gives you the choice to skip the entire thing with the Hover Wisp. It's not like it's even a hidden shortcut or secret that you have to seek out. You're probably going to take this route because it's the level where the Green Wisp is first introduced, and it's handed to you right there. It's a lack of quantity and quality at the end of the day. As you pointed out, the 2D to 3D ratio is increased if you include the recycled acts. Like it or not, you have to play through those levels to clear the game and they're also included in the Egg Shuttle (arcade mode, essentially). You spend more time in 2D than 3D, and much more time in active 2D gameplay than in active 3D gameplay. Furthermore, the true bonus content is the Sonic Simulator, which is almost entirely 2D by design. I still don't want to see more 2D sections in the next Sonic game, whatever it is. 3D and 2D are different beasts, and it's tiring that 3D keeps getting the short end of the stick either by quantity, quality or both. I want a fully 3D game that actually plays like a 3D game. Mortar Canyon in Forces is fully 3D and to some extent that's refreshing. But like you said, it's crap. I'd rather another hybrid or fully 2D game than one that's fully 3D in the style of Forces and Colours, because that kind of 3D is so insubstantial.