I would not have been happy to see a dent on a brand new car before I even got to drive it, but would give the dealer a chance to make it right. If there's no sign of it after it's fixed, I would be satisfied.
As for your NooB questions...
1) It seemed to warm up pretty quickly, even in -20C temps. Didn't notice abnormal noise. In the meantime if you have the heated steering wheel and seats, that helps.
2) There is a mute function on the infotainment screen, no button on the steering wheel. I haven't used it, so check the manual!
3) Manual says minimum 87 octane, so not really; but... using tier 1 gasoline might be something to consider.
4) There's a lot of technology in many new cars these days, so you may or may not agree with the way the designers programmed the behaviour of some systems. Just read some of the threads here about the radio, for example. The adventure is figuring out all the 'quirks'.