I don't think I will ever like aero wheels, Madrids for me. I'm lucky that I have a short commute though so the performance hit doesn't really affect me.

 

Still chasing a decent looking set of wheel.

Last night a really nice Perlecent white Kia Optima with black roof and de-chrome pulled into the carpark I was charging in while at the gym. It had the 18" Aero style wheel fitted. They are 5x114.3 Good quality Wobble bolts should work, bore is larger than golf, so i can get an adapter for the wheel. offset is ET46

I think they are a decent compromise between 18" and aero benefits. Id add a VW centre cap !!

 

As you've observed, the trouble is that making an aero wheel tends to make the wheel heavy which has its own impact on efficiency. The Tesla Aero wheel is designed to be as light weight as possible (and at less than 10kg for a factory 18" x 8.5" rim is pretty impressively so).

Since you've stated that a 5x114.3 could work, why not get a set of Tesla Aeros? If you don't like the look of the aero covers, then there are third party alternatives coming. For example, Rimetrix Orbital:

(admittedly they've just cancelled the kickstarter campaign for these, but they state they're going to relaunch it soon).

Point being that the Tesla 18" aero is already so ubiquitous and with the american tesla scene for modifications being very lively, there will be a number of options over time that people will produce for this.