keep it simple, pick your programming language first. Ue4 I do prefere over unity 5. but If I had to code as a first time coder I rather learn C# or JS because you can use both in unity. I do love UE4 But years down the road when I pick up C++ then I dump unity. At the end of the day it all depends on what your making, what Code your using, because blueprints is nice, But being able to write your own code for building a custom character
controller where your character moves in your game the way you want is priceless. Coming from a animation, Rigging back ground I have only one need and thats coding I can do most in a 3D pipeline. Just really strong in animating and rigging. I like Cry engine It’s got the best water and terrain in most engines with the help of world machine lol. But who doesn’t use world machine for there terrains.
And the marketplace, Because of Unity’s Marketplace it saves me alot of time. UE4 needs alot more content. Unity has some junk content there
but there are some real gems that are also on UE4’s marketplace like rifleanim pro.
If your new start off slow, If you have a team that knows UE4 use it. If your solo get Unity 5 personal and check out Marketplace theres a wealth of content. When you get better learn C++ and kill it in UE4. AAA titles better to use UE4 mobile better to use Unity. Other engines get lost in the rest.