Well, Unreal 4 has Blueprint, if you have no intention of learning a real programming language like C++/C#, and actually can get on with the Blueprint system (I found it not really useful, many did find it good), it is a more artist friendly engine in that sense.
True the Blueprint is one of the key features that makes Unreal better for artist but it isn't all.
Unreal import and exports better allowing for a work flow between engine and 3D software, very important for level design where the basic level starts as just cubes and stuff.
Unreal's material editor allows for full control of the shaders with no need for code.
Unreal has animation tools that allows you to pull parts from a animation and use it on other rigs, saving a huge amount of time as you don't need to do a walk cycle for every character, combining this with physics also allows for unique animation based on the skeleton.
The largest drawback from using Unreal is that it's made with professionals in mind, making it a lot less forgiving than Unity.
Unity is the better engine for mobile games at the moment as Gain-Reto pointed out and because of it's forgiving nature and documentation it's better engine for new developers.
It's not that Unreal doesn't have documentation on very thing, it's just that 90% of those documents say the same thing as the tool tip. If the tool tip was clear I wouldn't need to check the documents, so why does it say the exact same thing!
Even if I would, I'd say you can get multiple different visual scripting systems for Unity starting at about 25-50$ from the Unity asset store, and some of these are actually quite good. As tightly integrated into the engine as Blueprint? No. But still, its an option.
This is the thing I hate about Unity, just to have a proper workflow you need to buy so many addons for things that should have been built into the engine. It was fine when Unity was the best engine in it's price range, now with Unreal free it just feels redundant.