Congrats; beautiful color!
Here is my $.02 as a newbie - got my LR4 in April and have about 2500 miles now.
1) Sport mode - seems to drop one gear down no matter what speed you are going. Yes, it definitely increases the shift points upwards but I don't find it overly-aggressive.
2) taillights - I actually like the look of LR3 lights in the daytime, but the LR4 lights at night (illuminated).
3) nav unit - only complaint is the 2 second delay after pressing each letter using the "keyboard".
4) Horn - I just love those horn buttons. To me, this is so much better than a large area that "kind-of" works...you know, it's easier in the center but more effort required as you get further out. I can roll my thumb immediately over and hit one of the bars for a short "tap-tap" or long blast depending on what's needed. At least for me, much faster than quickly taking a hand off the wheel and punching at the horn in an emergency. A louder horn would be more appropriate for the drivers we have here in NJ, lol.
5) eco mode - lots of people have posted on this and I mentioned I don't have a major problem. I usually leave it on and turn it off when I want to. ONLY thing is that recently I have run into situations where the car shuts down "unexpectedly". Turns out if you take your seatbelt off and then release the brake pedal it assumes you are getting out and shuts down - surprise!
6) HVAC recirculate. I am surprised I haven't seen anyone mention this, as it's the most annoying feature to me (and I am not talking about the feature itself). When you push the button, the entire Nav screen blanks out to tell you that "Recirculate -Timed Mode" is activated, or something like that. Is this really mission critical information that you need to take my map away, LR? I use the map to know which street to turn down even though I do not have an actual destination entered. Happened a few times now that I missed a turn due to the "urgent message". Just funny.
Best of luck with your LR4.