Things to remember - you got your shows with out either of these two lenses. Ultimate sharpness is not the only parameter to use to sell successful artistic images. You may need the resolution and other improvements of the 14-24mm lens or not. If not, you will pay the premium of having the best without garnering the advantages. What do you consider pluses? Does the cost, weight, and lack of filter use mean anything to you? Only you can answer these questions, not me, not Ken Rockwell or anyone else on a board. Is having the BEST, and I use the term figuratively, push the issue. I have wealthy friends who buy stuff to just have, nothing wrong with that at all, but the two most talked about images I have were shot with either a FM and cheap Tokina zoom 20+ yrs ago, or a Canon Pro 1, about 4 yrs ago, both printed large to 16x20 or 20x30. That didn't stop me from getting a 5D etc. It all comes down to what you want and can afford, no one will think less of you if you use a 17-35mm instead of a 14-24.
Other factors, do you have other lenses in this range, are you happy with them, do you NEED a 14mm lens for your work, do you make large prints and look at them from 6 in. ?
This man's opinion is if I was thinking some day of a FF camera, I would go 17-35, it is wide enough and convenient enough, sharp enough to use. I would have a fear long term of an exposed front element, that is just me, but shit happens...
If I knew I was staying with APS-C format, the 12-24, is adequate at a fraction of a cost, sometimes I just go for GOOD value, cause the most important part of the equation is what is between your ears......