I traded my wifes 2008 Accord EX-L (fully loaded) for a used CPO 2009 RWD V6 SRX.
We couldn't be happier. We hated the Honda. It too was in the shop several times and when I traded it it still had two naggy issues they couldnt' fix. In fact one of the issues dates back to 2000 (dimming headlights or flicker) this is a copy of the TSB Honda is using to tell new Accord owners this is normal
The best Highway MPG I got from my 08 Accord EX-L I4 was 28 MPG. My 06 vette routinely gets better highway mileage. The best highway MPG I've managed with our 09 V6 SRX has been 22+ MPG.
We bought our 09 SRX because we needed more space and a wanted a more "upscale" driving/ownership experience, the SRX delivers that in spades. Plus it's American - which means a lot to this veteran.
As far as your poor fuel mileage is concerned I'd bet it directly related to all the error codes the car is throwing and should be easily fixed.
If the dealer you are using can't sort out your vehicle, I suggest you find a another dealer.
Good luck and report back when the dealer completes their trouble shooting and repairs. So the grass isn't always greener.