Not to get confusing, but the 2015 Optima has not been recalled for the engine debris problem, only 2011-2014, but along with the '11-'14, the 2015 has had the voluntary ecu update and when the update is performed, then the unlimited engine warranty would be in effect.Your not better off with a 15. All 14 and 15's have engine recall to update the ecm. theirs no difference at this moment, both are suspect engine but covered under lifetime warranty due to the recall (for bearing wear)
I think its an all around good car for the money. The ride is firmish because of the sport tuned suspension and crappy nexen tires. If you change the tires so a higher quality brand it will improve the ride quality. I had a Optima LX with the 16inch wheels and that had a softer ride quality than the SX with the 18inch wheels and sport suspension.Sounds about right. It doesn't pull hard off the line so much as you can feel it on the road. Think some of those things you mentioned might be part of the Premium or Technology packages.
Favorite option is the pano roof. Mine hasn't squeeked but have read about people taking there cars in to repair it. I imagine they try to clean off the rails and lube the rollers. Seats I'm ok with but they could be more bolstered. The ride is pretty firm to me. Didn't know about the LED tail light thing, thanks for mentioning it. Would trade paddle shifters for a heated steering wheel. You couldn't get both unfortunately.
Just wanted a DD to get to work, drive some around town and take short trips on. So far its been a great car for a great price, also bought mine used.