Honestly, most folks use STI's but adjust the reach to be shorter. That gets rid of a bit of the awkward nature. It's a pretty common thing to do. You can get away with that because the way the bullhorns curve where an STI would be mounted is such that you wouldn't end up colliding with the bar trying to pull the brake after adjusting the reach really short.
Honestly, what is posted above with separate bar ends from the brake just looks awkward as all get out.
Up to you though. I would try the STI's first and adjust the reach shorter if it were me.