Looking good :-) You can eliminate one bend in your return line if you run the line closer to that outlet side of your sump and tank instead of right smack dab in the middle. Running it in the middle like that probably won't work too well anyway because that line will probably run into the skimmer. That is unless that end of the sump (closest to the overflow) houses the return section of the sump and not the skimmer.
kinda like this..
Oh, and if you are going to put two powerheads there I would consider making the overflow box smaller. Leave enough room on either side of the overflow box for the powerheads. In the future if you ever decide to go vortex they won't work at that end of the tank with your overflow box the way it is. Plus, adjusting the powerheads up and down or removing it for cleaning will be a royal pain in the ass if you have to fish out that magnet out of your overflow box.. trust me, been there tried that! I suppose you could put the magnets on the display sides of the tank. That wouldn't be too bad I guess.