Things that definitely DO make a difference are Performance Pack.... that definitely makes sense, you'd have been crazy to buy a Mk7 GTI from new without it.
Not because OMG 1000000mph, but simply because it really is THAT much more desirable down the line.
Sunroof maybe, leather maybe..... its the things which let people see what they are getting. But the "extra" will be a fraction of what you paid for it.
DCC....rear camera...park assist...navpro...HK...heated seats... meh can't see it, won't pay for it. Wheels? Nope, tyres are more expensive, wheels can easily be changed.