Honestly no, If the WiiU isnt your first console, chances are it doesnt have the type of games you want to be worth getting as a second console

If all you have is a PS4, i would recommend a 360.
If all you have is a XBO, i would recommend a ps3.

Both are cheaper than the WiiU, both have infinitely more games, which are also much cheaper, and both come close to or are on part with the WiiU graphically.

It depends on how broad your tastes are. If you have a wide range of tastes, than yes, it is an excellent secondary console. If your tastes are more narrow in focus, than perhaps not unless Platformers happen to be within that focus.

Well it's pretty much the only second console after you already have a PS4. It's not a great console but it's not like you have a choice.

Implying it isn't a good first console?

It is fantastic

If you like to play anything other than Nintendo games, it isn't. 

I'm a Nintendo fan but I couldn't in good conscience reccomend it to a friend who I know likes third party games. 

Depends.

Do you like playing the same games you played on the Wii with only slight improvements made?

Citation for this remark:

Wii U: NSMBU, Mario Kart 8, Donkey Kong Country Returns, Pikmin 3, Super Smash bros 4

Wii: NSMBW, Mario Kart Wii, Donkey Kong Country Returns, Pikmin 2, Super Smash Bros. Brawl

It's not to say that these games aren't "good," but after owning one for a year and then selling it, I can't recommend the thing.

Just get a Wii and draw a U on it. It's literally the same thing.

Yep, the Wii U is far more differentiated than XBONE is from PS4.

This is true, PS3 & 360 are >>>>>>>>>>>>>>>>>>>>>>>>>>> Wii U.  But, I wasn't including those since I already had them.

Of course it's a good 2nd console, but it could be at least 100x better if it didn't come bundled with a gimmicky, useless toy.

Absolutely! It's my local MP console right now though some Plus games have surprisingly filled that gap as well. Can't beat Mario Kart if you have 3 friends to play with though (I have two apartment mates that play with me so if we have someone over it's great fun)...oh wait yes you can when SMASH comes out!