Luigi's Mansion 2(Dark Moon)>Luigi's Mansion
Mario Kart 7Melee
My thoughts

Graphics wise, Gamecube is more powerful, but 3DS mostly makes up for it with better shader tech. Next gen handheld will undoubtably surpass Gamecube, maybe even Wii since Wii was only a small step above GC.

I should hope so, Xbox One is a current gen console :P

The Wii was barely a step above the GC, so the next Nintendo handheld will most likely be somewhere between the Wii and the WiiU in terms of visuals!

The 3ds while playing lookk much better.

So, around par with the Vita, then?

Maybe a bit ahead, similar to 3DS vs PSP

So there is no handheld more powerful than a home console regardless of generation differences? Vita less powerful than a Super Nintendo?

In terms of the OP I would say you'd be hard pressed to find a cpu intensive game on the 3DS like Pikmin 1+2 where you had the gamecube handling the AI of up to 100 lil guys and anywhere up to 30-50 enemy AI at the same time all in some of the most realistic environments to be found in the 6th generation of consoles.

What you do have on the 3ds tho are some utterly beautiful games like Resi Evil, Mario Kart 7 , 3d land and monster hunter tri/4 which hands down would not be possible visually on the gamecubes hardware... that said all those things have rather small environments and not a whole number of AI which are all active at once.

3ds is less powerful than PSP, but developers know how to make graphics look better.

A single 333mhz processor ripped from a now 14 year old PS2 hardware running at 200mhz to not have it toast your hands coupled with 32mb of ram is more powerful than a 3 year old Arm11 dual core loaded with 128mb system memory and 6mb of Vram? How?