First, sorry to hear about your accident, I hope everyone got out of it and is doing well.
Moving onto your question:
2014 is the first year after the refresh of the 4th Gen, so yes there are some body style differences, different hood, front grill, foglights, headlamps have black housing, LED tail lamps, new wheels and color matching and rounded side view mirrors. Interior wise, biggest changes are as you state: Push button start, dual green audio/navi and the marketing gimmick of the decade, the vacuum in the trunk for TE (at least to me it is...). Another big plus the 2014 has is that Honda made some updates to the chassis and strengthened it to do better in a small overlap accident, and overall chassis rigidity has been improved. [it should be noted that 2011 - 2013 still did better than any competitors, there are some threads on this].
The biggest negative of the 2014 in my opinion (and many share this opinion) is the Navi lockout when the van is in motion. So if you have a passenger they cannot input an address or POI in the navi while the van is in motion. Next, I personally don't like that they did away with the little tray under the audio commands that the 2011-2013 have, they also moved the USB from the glove box to center stack just below the audio controls. I liked it in the glove box so that my iPod could be out of the way. 2014 also only has 1x 12V outlet in the center stack, previous years have 2x 12v outlets.
We have a 2011 TE, the only thing I wish we could have from the 2014 is the proximity key / push button start and the improved chassis. Other than that, interior wise, I prefer the knob audio/navi controls because I think they are faster and cleaner [plus I have problems with finger prints on stuff so the touch screen would drive me nuts] but adding to that the navi lockout when van is in motion really kills the deal for me. Exterior improvements, the new blue color looks great, I saw one at the dealer the other day. We live in Florida, our van is white and honestly, I don't find the white looks that much better with the new design so that's just personal taste.
Comparing 3rd and 4th gen. Well biggest complains that I remember reading about is styling
Other than that, some miss the 2nd row captain chairs. Also if I remember right the 3rd gen had adjustable pedals, 4th Gen does not. Also, I think some have said 4th gen has less room for the driver (I'm not too tall so I'm ok, I just find the dead pedal to be way too big though).
We test drove a 2010 before buying our 2011 (both vans were new) and I thought the 2010 touring we drove was much louder than the 2011 we bought. However, be careful and drive the van you are going to purchase at highway speeds because 2011 - 2013 have a wind noise issue (ours did, we had the TSB fix and it was resolved). Now I read that some 2014 have whistling noises that seem to be coming from the windshield seals at the top or bottom of the windshield.
Make sure you comb through the ody you are about to purchase. They seem to be putting them together in a bit too much of a hurry. Some in the past I know had paint issues, others have had door jam issues where water would get past the rubber seals. With ours I'm noticing now that on the tailgate some rust seems to be showing through the pain. It looks like yellow/orange dots in some areas showing through the white paint.
Anyways, I'm sure I'm forgetting something but someone here will most certainly fill in what I've missed.