I run into this question all the time.
Every time someone around where I live asks me which C4 to get I tell them the same thing.
“The one YOU like.”
To me each year has something to offer and they are amazingly unique when you take the time to actually drive each one and get to know them.
I’m an early generation snob which I will fully admit. I like the earlier models all REAL digital display dash with real information. But again that’s just me. Some love needle gauges and there is nothing wrong with that. Its what floats YOUR boat that matters. Not mine.
Convertible vs coupe depends on the person and how they plan to use the car. Daily driver or if you need to take a good bit of luggage go with the coupe hands down.
If its a weekend toy like my current 87 convertible is then get a convertible hands down. The convertible is so much easier to get the open air effect with. The targa top is a royal squeak and rattle infested pain in the butt. That said it does make the car more rigid if you autocross it.
The wife and I went on our anniversary in the convertible last year and packing it for the trip was a royal pain and quite challenging. Where as we once bought a full size window air conditioner and brought it home along with groceries in the 86 coupe I had then.
Transmission wise the 4+3 catches grief but I never had any issues with it in my 86 coupe and once you pass someone just by pressing down on the gas pedal and the feeling the car downshift ON ITS OWN without you touching the shifter or the clutch pedal your hooked.
Unlike most car lines there is no bad C4. There isn’t a lemon year.
Main thing is try out as many different years as you can. Don’t let any persons opinion as to what year is best cloud your judgment. After all we’re not the ones that have to drive it, you are.
Just some of my random thoughts and opinions on them.
Back to my vette