the first home console i played on, which was the gamecube. i have so many fond memories of that console from when i was younger, thanks to games like luigi's mansion, super smash bros. melee, super mario sunshine, paper mario: the thousand year door, pikmin 1 and 2, and quite a few others.
the wii was pretty enjoyable too imo. getting every last star in super mario galaxy 2 was both fun and very challenging (ESPECIALLY at the end), and super smash bros. brawl and mario kart wii were also loads of fun. still, the wii wasn't as enjoyable to me imo.
as fun as playing splatoon, mario kart 8 and smash 4 online are, the wii u also isn't better than the gamecube to me. it just doesn't have enough games, which is a shame.
as for the handhelds, i've only really played the ds and the 3ds. the 3ds is the better one of the two imo - even though i have less games for it, i've found them to be more enjoyable than the ds's. i think it has the best animal crossing game in the series (new leaf, of course), and i've also enjoyed other games on there too, like luigi's mansion 2, pokemon y, and more recently fire emblem: fates. again though, i still think the gamecube was better than the 3ds.