Upload & Sell: Off
But after recently purchasing the 35 1.4 prime and falling in love with the sharpness and overall quality of the images, I'm tempted to purchase another prime...
That's the million dollar question. It's very personal and takes a lot of consideration.
The 2.8 zooms are very muscular lenses - they'll get you the shot and are flexible when space is limited. In comparison to precise primes which are more demanding to use - you have to position yourself well.
I do own a 16-35 f2.8, but as far as primes go I use a 35 f1.4, and a 85 f1.8 with a 135 f2 over the 70-200 because it requires a different approach and makes me work a little harder in terms of camera position when photographing dynamic scenes.
It also requires two bodies.
There's a reason the majority of press photogs use the 2.8 zooms, and that's that they are more likely to get the shot being able to quickly zoom in or out and frame the scene. Primes in the same situation require a heightened sense of where the action will be.
What tips me in the direction of primes is two things; the discipline of photographic practice, and the optical qualities each prime has.