I had this car back in March this year. Agree with most of your experience/comments on this car.
For the interior, I do find the US version of the Sonata, even for the Hybrid version (at least those owned by rental companies) are always the most basic version that they will have, which is a pity as a mid-tier version would have much better interior and functions.
I guess most important point for this hybrid vehicle is that it is indeed very fuel economical and the pick up when you do press on the accelerator is not too bad. All in all, it is not too bad of a car especially since this is the basic version within the model.

On a side note, I do (no idea why) prefer the Optima compared to the Sonata from both design and drive point.

Cheers!