My 2012 Model Year F10 520d SE is now just over 2 weeks old and I'm loving it. (Pics and spec in the Gallery section:
http://f10.5post.com/forums/showthread.php?t=598432)
The new model year build adds a few extras at no cost, which may help to swing the new/second-hand argument. The new "Eco-Drive Pro" gives new settings for economical driving (when/if you want it!), via an extra switch position on the dynamic drive control. Autos now get engine stop/start (the manuals had it already), which can be switched off whenever you don't want it. (CO2 emissions drop to 123 g because of these extras and I think the mpg goes up (can't remember what it was before...)).
But, as you are going for the media pro navigation, the best new addition is the new GSM-based Real Time Traffic Information, which gives significantly more info on hold-ups than the previous TMC radio-based system, offers sensible re-routing and even colours roads according to traffic flow. The resolution of traffic problems in busy areas is something like 50m!
I will add my support to the adaptive xenon calls... they transform the car at night (and look pretty cool in the daytime too!). Colleagues who did not order them are deeply regretting it now.
I'll also add my support to the sports-auto camp. It's said to be the best value option that BMW offer and (once I've completed the running in) I reckon I'll use the paddles as much as I did on my previous E60 530i. (It's not just about the paddles though, it just offers more flexibility... and the changer looks better!)
The internet function is a waste of time and money in my opinion, especially when you have iPhones in the car anyway. It's dreadfully slow and has a useless interface. It's my only (slight) regret in my long list of toys - but at least it didn't cost much.
iPhone connectivity using a snap-in cradle and the full iPhone interface allows video playback and supports apps from the iPhone (inc internet radio (which I use a lot, despite also having DAB) and social media sites). It also allows things like remote locking of the car from anywhere, remote flashing of headlights and sounding of horn, (to help find the car in a big car park etc) and also remote sending of google map positions to the nav system (I find that very useful). This latter feature also tracks the whereabouts of your car (and you) on the phone navigation screen - i.e. showing the quickest route back to your car (or presumably, where it is if stolen - although BMW can do that for you, afaik). To be honest, I'm not quite sure what you get of the above list if you don't include all the iPhone connection options and dealer-fit media cradle. As you mention, it's a bit of a nightmare sorting out just what you need, so I put it all in the hands of the dealer, who did his homework correctly and came up with the right spec!
I have the same 18s as you - I like the look and the ride, but I do also have VDC, so I don't know what they are like without the variable control...
If you are after any savings - I am really impressed with the standard black interior trim (and it goes beautifully with oyster/black dakota). It's a kind-of speckly finish, as though it has small mica or metallic flecks in it - and was a real pleasant surprise to me, as I had chosen it (or rather, left it by default!) to save some expense against my toy list. No regrets whatsoever!
I do have the smokers pack deletion. I think it was the right thing to do, but the extra space is not well designed. I just didn't want a "smoker's pack" either.
Can't think of any other points in particular... it's still a very new toy for me too! As with others here, feel free to ask any questions.