In my experience, road noise will always be the most prominent noise inmmost cars, except on smooth asphalte road surfaces, where slight wind noise then begins to redominate on motorways in my Karoq. I significantly reduced road noise on my MY19 1.0SE tech DSG a year ago, by amongst other things, going for AW tyres, switching to 16" wheels at the same time.
SELs may not be the quietest option as they have removeable rear seats which means they have the roll top boot cover. Fixed rear seats on cheaper models come with a more solid rear shelf which reduces road noise to some extent and I found that there was further mileage in damping down that shelf with wooden stiffening battens fixed to the shelf underside and putting some heavyish matts on top of the shelf. A bit extreme I know but I'm fussy and I do find road noise wearing in any car, even though I don't listen to the car radio much.
CAR magazine in early tests noted that the 1.0 was the quietest of all the engine options and I must say I find engine noise is almost undetectable in most driving, including motorways at up to 90mph, even after my road noise reduction efforts. There is a very slight roughness at idling when cold and a minor drone between 1500-2000rpm, when the engine is working hard say on uphills. With the DSG it is easy to change to Sport mode and increase the revs outside this range, not that it is a big issue really. 4cyl engines will have some sort of minor drone too, somewhere in the rev range, but you may find the 1.5 much easier to get hold of.
The SE tech came with ACC and I love it despite it's foibles. It was one of the few versions to be so equipped as standard. It's even better working in combination with the DSG. You'll be lucky to find a second hand 1.0 DSG though, as they stopped making them in 2019 and I was very lucky to find the SE tech version when I bought mine. I preferred the equipment supplied on the SE tech to the SEL option.