Personally I prefer the Q4 out of the rest of the VW group (i’d 5 Enyak etc). As you say it doesn’t adopt the big box little box theme on the dash.
The Q4 like the rest of the group has indeed had some changes to the battery software/management and new AP550 electric motor, meaning the are up from 201bhp to 286bhp, with a range increase to 330 miles and 349 for the coupe WLTP. 0-62mph has reduced from 8.5s to 6,7s,
The EV6 is also a nice car, with plenty equipment more the the Q4, id’s etc but, its the mid range so misses out on leather seats the Q4 has, as standard, if that is important. I think it sits a bit lower than the Q4 if I remember.
Either the Q4 or EV6 are nice cars, with more logical interiors and have similar range.
Have you looked at the Ioniq 5?