These don't quite fit all of your criteria, but for cost effective, aero, strong, and relatively light ... the old Rolf Vector Pro. Haven't been made for a couple of years, but you can find them used on ebay in the $250/set range.
Aero - very. Aero rim, low spoke count, bladed spokes.
Missing spokes - yes. 14 front, 16 rear, but they're bladed spokes and torqued to a zillion foot pounds.
Lightweight - 1800g a set.
Strong - rode mine for two years, they are still true. DT hubs, plenty strong.
Downside to the pro's: it takes a trained mechanic to true them, and they're very stiff - I finally bought a set of Campy Zondas to get a bit softer ride. As for truing - never have needed to get that done, so I wouldn't know.
But you can't beat the Rolfs for their combination of performance and cost. Every bit the equal of Kysriums at a lower price. Personally, I think they look cool, too.