Dont have a wii u, plan on getting one next year, but this monster hunter is also avaible for the 3ds. I actually dont plan on playing online at all, is this a good choice for a first monster hunter? Should I wait for a hopeful release of Monster Hunter 4?

Get it now, the earliest we'll get MH4 is holiday 2014 imo. Wii U is the better version but you only got 3DS! You'll be playing hundreds of hours so $40 is very good dont you think?

Hard to say.

If you want to get into MH, online/multiplayer is pretty central to the whole MH experience. MH3U for 3DS doesn't have online.

We don't know if MH4 will have online in NA either.

If you had a WiiU then I would say getting MH3U would be nice.
But I'm going to recommend skipping MH3U for 3DS unless you have other people to play Multiplayer with.

I never were going online with Tri and had a lot of fun. But yeah, online should make it sweeter.

I feel like capcom should be way more confident in Monster hunter in NA, monster hunter tri had a great start here

exactly, if NoA+Europe get more into the franchise(which it is) then MH4 can be a 6mil hit! Why? Japan alone can do 4.25-4.50mil while NoA does 750k and Europe 750k + rest of the world!!!

MH is a franchise that takes a lot of time to get into. I recommend you watch a lot of videos before buying the game. Online is a very important aspect of the game but you can do all the missions offline so there's no big issues about it.  

I heard that MH 3 Ultimate makes some things "easier" for new players, like having all weapons types at the beginning so you can choice your favorite very early and having a better starting armor. 

I recommend you watch this video before making your decision, he's my fav reviewer and he makes some great points about the game. 

It's quite fun in single player as well, but online is the best part.

Well if you are planning on getting a WiiU down the line then go ahead and get it for the 3DS (assuming you don't mind paying for the game twice).

You'll be able to transfer your save file from your 3DS game to your WiiU game.

I got both a 3DS and WiiU copy, so when the WiiU is in use (most of the day by my wife and daughter) I can work on the game on my 3DS then transfer the file to the WiiU when it is free. Both versions are good, the WiiU is better. Both are improvements on the Wii version (almost 200 hours played on that one).