If you are going for a Belgian Blonde this looks great. If you want a Belgian Golden Strong, like Duvel, then I think you could make some tweaks.
I get an OG of 1.089 (assuming 70% eff with your partial mash setup) with these items in 3 gal, which I think is a bit high. If you do this right, it should end up below 1.010 so you don't need a huge OG to get 8-9% ABV. 1.075 is a good target. If you increased volume to 3.5 gal you'd be at 1.076. You could also drop the wheat LME or lower the pilsner DME, as they will tend to raise the FG a bit. You could also drop the aromatic, as I'm not sure it goes too well in a GS, but such a small amount probably not a big deal. I would definitely swap out the Candi sugar for just plain old table sugar. IMO, in a GS you don't want any of those carmelized flavors that these sugars are made specifically to provide. Plus, it's way more expensive than sucrose.
Mash low and give it a while (at least 60 min, I went 90 with full AG), around 149. Maybe even throw some of the extract in with the mash if you have room for some additional water and the extract. You will lose a bit that might get absorbed in the grain, but you might also be able to break up some of the higher-chain sugars in the extract. Never tried that trick, but heard about it and seems plausible.
Also, I think late addition hops are not necessary. You can get all of your bittering from a single 90-minute addition and reduce the residual hop flavor. This lets the malt and yeast character shine through in the finished beer.
Make a yeast starter for the WL golden strong yeast, which is WLP570. It's a great yeast if you start temps low, in the low to mid 60's, then gradually rise to high 70's over 10 days or so. IMO, you really need ferm temp control to make this yeast perform to its fullest. The Wyeast "equivalent" 1318 is not the same, tends to take a long time and flavor profile is different.
All that said, this is just my advice based on a version of Jamil's Belgian GS that I really enjoyed. So take it, or leave it and go your own way and tweak based on your results. It's a great style, and a good one for impressing your friends, or converting your skeptics. Cheers!