PS4 does not "require" and online subsciption. Most games require PSN sub to play online multiplayer.

Also add Reshogun to the list of games kids might like. If you ever played the old Gradius games its kinda like that.

Minecraft isn't a problem, as it's available on Linux. Fifa 15 kept the kids interested for a week or two on Wii, Fifa 2010 WC was a game for a month or two - Mario Strikers was played for two years.

I usually judge if a game fits my kids by playing it by myself, otherwise I go along the lines with PEGI.

The countless LEGO games, sports games, Rayman Legends, Gravity Rush 1, 2, Ratchet and Clank, Tearaway, Dragon Quest Heroes 1, 2, Dragon Quest Builders, Dragon Quest 11, Kingdom Hearts 2.8, Kingdom Hearts 3, Dragonball Xenoverse, Gran Turismo Sport, Driveclub, Littlebigplanet 3, and dozens of downloadable games like Flower, Journey, Minecraft, etc.  The Last Guardian will probably be rated T.  Also if they like or want to try the more niche JRPG titles there's games like Tales of and Disgaea.

Edit: Also all 3 original Uncharted games are rated T so you can get the Uncharted Trilogy.  Not sure what Uncharted 4 is rated.

I say ps4. A lot of diverse games have and will be announced. Child friendly and amazing games such as no man's sky, rocket league, boundless, gran turismo, and adult friendly games such as uncharted, horizon, detroit

Wii U is definitely your best option right now considering you are trying to make the best decision for your kids. You have to consider that whether you choose Wii U or ps4/xb1, it is going to be a trade off anyway. either it is wii U due to having the highest amount of games accessible and suitable for kids but no minecraft or updated fifa game or ps4/xb1 but no mario and other accessible games. If I were you, I would definitely pick up a Wii U for them. the amount of games that you will have at your disposal between the amount of games that you will have to sacrifice is better on Wii U in your case.

Yeah, I know it's a bit redundant, but for family friendly entertainment, the Wii U is a great machine. The PS4 and it's strengths and game selections have been covered fairly well also. The Xbox One gets the most play from my family and I (6 and 9 year old kids), with the Wii U right behind it. Funny enough, PlayStation gets more attention in my house for more of the adult games (Uncharted, Last of Us), but not much else.

Admittedly, I don't restrict games based on ratings alone (maybe I'm a bad person/parent) but I am pretty open to anything as long as they behave and their good behavior continues (inside and outside of videogames). Anyhow, a lot of the family friendly content that gets heavy mileage on Xbox is available on the PS4 (Minecraft, Rayman, Disney Infinity - the most expensive gameplay experience available, and Goat Simulator). However, Rare Replay has quite a few great family friendly games within, namely the 3 Banjo Kazooie games, but there are more, depending on your taste. Ori and Blind Forest is a nice game as well, and we've ha some fun in Powerstar Golf and Happy Wars. Zoo Tycoon and Screamride are decent in short bursts for us as well. My son, the older of the two, has sunk a lot of time in Project Spark on Xbox. Forza 6 is real solid too. Those all are, for the time and to the best of my knowledge, only on Xbox (at least in terms of consoles).

All 3 are great platforms with unique strengths and weaknesses. I don't think you can really go wrong. It is a shame that the Wii U has so little support from anyone other than Nintendo, but their titles, and the expansive catalog of past generation titles available for it make it well worth the price of admission for us. Plus, with the NX coming sooner rather than later, my biggest fear is that they (and you) will feel abandoned on the platform. That's not nearly as much of a concern with the Xbox or PS4. And again, either of those are great and even quite similar, which doesn't make you decision an easy one.

I'd be glad to try to help more if you can think of any questions or concerns that you want to run by me. Good luck!

Personally I would say Wii U if it is strictly for your kids. I own a PS4 and a Wii U and kids really like the Wii U more than the PS4 from what I have seen. If adults will play it to a PS4 is still a great choice as it has way more child friendly games than most people on here realize.

Also saying FIFA did not last long on the Wii does not mean it will not last long compared to the PS4. The PS4 is a full 2 gens ahead of the Wii in terms of tech

Well there's your answer.

If all you want is a White Premium 32 GB Wii U you can buy one from the Nintendo Store. - https://store.nintendo.com/ng3/browse/productDetailColorSizePicker.jsp?productId=prod610428

White Wii U Deluxe + Super Mario 3D World + Nintendo Land Bundle - REFURBISHED - $235.00

Included in the set:

•  
  • Wii U console (White/32GB Internal Storage*)
  • Wii U GamePad (White)
  • Super Mario 3D World digital game
  • Nintendo Land digital game
  • Wii U AC Adapter
  • Wii U GamePad AC Adapter
  • High Speed HDMI Cable
  • Sensor Bar
  
  Wii Remote+ Controllers not included

Given the age of your Kids, and given that you already have a WiiU, PS4 is prob the best bet due to a wide range of diffrent types of games, with the posibiliy of Virtual R taking off, I think PS4 is prob your best bet.