I am currently looking for tires and rims for my 2014 supercrew 4x4.
I plan on installing a 2.5" leveling kit so I want to fit 33" or 34" tires with blacked rims (preferably more rubber the better)
Is there an aggressive looking off-road tire but also fairly decent for mainly road driving?

 

34's should fit fine. Others had success putting 35s but they did some minor trimming.

 

I'm in the same situation. I was going to go as big as possible without a leveling kit, but I think I've changed my mind and will get either the 2" or 2.5" kit. I'm downsizing from 18" rims (with 275/65R18 tires) to 17" rims to get more rubber, then increasing overall wheel diameter to around 34", and creating a more aggressive/wider stance (at least that's the hope).

In my research I've heard good things over and over about the Nitto Terra Grappler G2's. I was leaning toward those, but I want a more aggressive-looking sidewall tread, so now I'm thinking the Kanati Trail Hogs (imitation of the DuraTracs, but around $100 less per tire). I'm hoping to level the truck, then add 17x9 ET25 black rims and 305/70R17 Trail Hogs. If this set-up actually fits, my wheels will be 33.8" in diameter and stick out about 1.5" farther than the stock wheels currently do. I just need to dial in the right rim width and offset to make it work. I may need to do some trimming too...not sure yet.

Another tire for you to consider is the BFG All-Terrain T/A KO2.