Agreed completely. Carving performance is really important to me especially. Nothing matches the performance of a race inspired ski <73 mm underfoot. Its even more noticable on days approaching the feel of an injected FIS course. You CAN carve something wider, but I can enjoy a frozen day on a ski like that, much less fun flapping around on a 95 or even 85mm ski.
Same thing goes for real mogul skis, though I've only spent individual days on them and can't zipper moguls well enough to really feel confident touting their superiority in detail beyond "wow."
All mountain skis these days can do just about anything okay, but just as 117s really rock, a 67mm also shines in the right scenario and conditions.
Several years ago I tried using my Fischer RX8 skis (mid 60s at the waist) and absolutely couldn't stand them any more. Back in the day I loved my Atomic Beta Race Carve 9.something skis (although back then I loved just ripping down groomed runs with big GS turns and skied VT only maybe once a year)
My current quiver only has 2 skis:
Volkl AC50 (85)
Nordica Hell and Back (98 )
The AC50's are my hard pack/early season/late season skis. I enjoy the playfulness more on the Nordica's though as long as we have at least packed powder conditions. Can't really speak to wider skis as I haven't had much experience with them in the right conditions. I've toyed with the idea of getting something wider for true powder days but just couldn't convince myself to spend the money. Generally speaking my current skis do quite well in east coast conditions, although I fear the AC50s are approaching the end of their useful life and may need to be replaced in the next couple years.