Nice job on the tarp! Yes, a cantenary cut will cut down on those wrinkles, but you might want to lower the whole pitch a little (allowing you to use the front pole outside, freeing up your interior space) and pull those front two corners a little more forward also.
Pitching in the wind can be one of the most frustrating times to peg down a tarp shelter, especially if you are solo or new to a particular pitch. One of the quickest and easiest ways to pitch an "A" in wind is to stake out the back corners to the ground, then put up your front pole and front corners. Put up your back pole and readjust the rear corners. Finally peg your sides out, and readjust everything that's lose or flapping. The key is practice. Also keep in mind the windier it is, the lower you'll want your pitch to help shed wind and weather.