Eh, I prefered the 64 version. It had the right balance to difficulty and fun. I prefer the game as it relies more on the character's skill at controlling Mario rather than relying too much on powerups (which would explain my fondness of Genesis Sonic games).
SatAM was taking a, at the time, rather storyless project that was pretty light hearted in appearance to something a bit more storydriven and darker. Nintendo's would be Advance Wars Days of Ruin compared to the lighthearted Advance Wars series. Metroid doesn't fit as it was already dark.
I mean Samus has lights on her armor for a reason.