My thoughts, for what it's worth. The performance Golf is so well specced these days even the standard car doesn't disappoint. The only extras I felt compelled to add were metallic paint, the climate screen and the rear view camera.
Nav Pro - never had it, but the standard MIB3 nav is a big step up from the MIB1 I had in my Octy both in terms of sharpness and responsiveness. However I spend far more time looking at the AID than the head unit, so unless you really need nav on both screens, or you fancy a game of charades with the gesture control, £1k is alot to shell out.
DCC - haven't tried 19's but the standard suspension is absolutely fine with standard wheels riding on rock hard Bridgestone rubber. If anything i'd say it's a bit more forgiving than the suspension on both my previous cars with same 18 inch wheels. But if you're really unsure it may be best to arrange a test drive so you can decide for yourself.
Leather - the new style leather in the 7.5's does look lovely from what i've seen of it in the GTI, but the £2k cost is just ridiculous to me. The biggest issue I have with the Golf seats is the seats themselves, not the fabric. The red jacara fabric looks fantastic to me, but if you must have something to set it apart the art velours seems a good compromise.
Sunroof - most of my driving seems like it's either done in the dark or in the rain, so i'm not sure i'd see much benefit. Besides I do quite like the dark cabin, and sunroofs add weight, they can sometimes rattle, and they reduce headroom.
Keyless - i'd probably tolerate it if it were standard but i've never really seen the appeal. Had pushbutton start on a previous (Ford) car, and just felt it was a pointless gimmick. The recent scare stories about theft only strengthen my opinion. However that said, lots on here seem to swear by it, and if you really believe in it then it's unlikely a stranger will change your mind.
Lane assist - I had it on my Octy as standard fit, but didn’t use it after the novelty wore off in the first week. That said though, I did have a Qashqai for a few days that had the blind spot monitor, and was actually quite impressed by it. Very useful on the motorway.
As others have said, all 7.5 GTi's and GTD's now get larger tailpipes.
From what you've said in your other posts i'd be tempted to keep faith with your current (and still very nice) GTD, and then go for a Mk8 GTi or a Karoq Sportline. However i don't doubt a Mk7 GTi would still put a beaming smile on your face. In any case, good luck in whatever you decide.
