I guess the biggest example of the open world aventuring/collecting that iffed me a bit in Sunshine were the blue coins. They were just this random element put into the game that led to the collection of more Sun Sprites. It seemed very Banjo-Kazooie to me (like finding the musical notes and the Jinjos along with the Jiggies). Not that that's a bad thing to have in the game, but it was just something that I never got into (and Sunshine is the only mainstream Mario game I've played where I never 100%'ed it.)

64 had a similar structure with the 8 red coins, and Galaxy 1/2 also has some of that with the purple coin challenges. Although with Galaxy, many of the purple coin challenges are more about successful platforming rather than exploration, not to say that there's none of that (the HoneyHive Galaxy's purple coin challenge is a good example of a non-linear challenge).

I tend to like a mix, which I'd say Galaxy 1 probably comes closest to honestly. Galaxy 2 is a lot tighter, more focused, but much more linear.

64 was a classic, but Sunshine was honestly an unfocused mess. Way too much collectathon padding too, you could tell they rushed that game out the door.

I only like open world levels when it leads to more then one way to accomplish a goal... and even in mario games... that's a huge rarity.

It's like RPGs which large expansive worlds... but nothing of interest in them otherwise. No point.

Sort of agree with you as it would be cool to have more than one way to accomplish a goal sometimes but since when has mario been about open ended levels, although 3d does open the door for this.

 I don't see Nintendo changing the formula for 3d mario, in terms of linear/open levels any time soon so if you want open world levels your probably better off with a different game.

... and umm how do you start threads on here ? :S

@ OP  It's funny that you say this.  I was playing SMG2 earlier today and was thinking about how I missed some of the exploration.  This is what made the forst two 3D Mario games different.  In SM64 it felt like you were exploring an entire world.  In the Galaxy games it's more like the classic 2D platformers with the go from point A to point B approach.  I'm not saying that I don't love this type of gaming as well, but choosing this approach with both styles makes them a little too similar IMO.    

I have not played Mario 64 in ages, so today I got my 64 out and played it. I have to say, while I already new which style I liked more, replaying Mario 64 just seemed very lacking to me. I think it is safe to say it felt like nothing more than a scavenger hunt. While I enjoy exploring in JRG's, Metroid, Zelda, MMO's and some other games, I just do not think I can do it ever again in a Mario game. At least near as much in that game. I still enjoy finding all the coins and stuff, but to make it the focus is meh.

Look at this face.  Does this face look insecure?