There's a number of consumer issues if you research but keep in mind there are a lot of C8's on the road and the problems always hit the news first and shouldn't represent all C8's...
They had some engine problems with the LT2 back in the inaugural year but thay seems to be resolved and supposedly it was only on a 3 month run of engine builds. There have been some rarer issues with the DCT that range from pretty minor to blowing up. The hood flying open on the road was resolved pretty quick. The hydrocarbon pads coming loose and triggering the check engine warning, the comparable lack of cargo space, water entering the engine compartment when the car is washed...Might happen in the rain too but no one drives their Vettes in the rain... lol....A transmission that requires a full service every 12k, Over the air updates leading to a car that sometimes won't start... Basic servicing costs are 3 times higher than the C7 if you don't do them yourself (and endanger your warranty).
Now. Just to be clear, there are a lot of C8's sold that haven't had any issues...yet. So time will tell.
Many will say yeah. But the C8 is a totally redesigned car from the C7 so there's bound to be growing pains... True... But the C7, other than the air cleaner and the removable roof latch was also a total redesign from the C6, and other than a third gear shift shudder in the automatics, the C7 Stingray was a no recall, no issues, solid problem free sportscar.
There are lots of things on the plus side of the C8. Better traction for those who want to winter drive, better handling they say as I haven't driven one yet, but really, after you can pull 1.2 g's in a C7, unless you're tracking you car, what more do you need...The C8 boasts a top speed of near 194 mph...the C7 only 190 mph but who's going to test that on the road, 0 to 60 times for the C8 are about 2.7 seconds I believe while the C7 is about 3.6...again .9 of a second wouldn't make or break my choice when back in my muscle car days my 340 Duster was 5.7 seconds and we thought we were flying then...
Don't fret your choice. I love the looks of the C8 but I love the looks of the C7 as well, and the few differences that compliment my driving habits more than anything make the C7 more attractive to me.