I wonder what would have happened if around 66/ 67 (drugs taken out of the equation) if Brian, Carl and maybe Dennis had left the group, and done their own thing what would have been the result? Maybe a Wilson/ Flame vibe but without having to do the old BB stuff in concert.
I agree with a lot of what you're saying.
Question about your hypothetical. do you Brian, Carl and Dennis quitting the Beach Boys to start a band together or do you mean all three going solo? It's hard for me to imagine what might of been because Brian was so fried and not that interested in music anymore. If Brian had not gone insane maybe he could of had the power to dissolve the Beach Boys. Imagine if he quit the group and started writing and producing records in direct competition with them. How could they have survived? The Beach Boys would have been obliterated.
Yeah I meant the three doing something together and the drug thing with Brian never happening. Just a concept and nothing else.
With the drug thing never happening we'd have better albums after Holland, even with the burden of non-Wilsons in the band.

After Holland Carl seemed to be distracted by problems with drugs and his marriage. He had always been able to come up with good product since the sixties. After Holland he wasn't as much there anymore and then there was the Caribou fiasco, the 15 Big Ones disaster, and so on.