I multiclass not necessarily because I'm min-maxing, but because I enjoy the creative combinations of abilities that I can put together, and because I think of single-classing as somewhat boring at times.
With that said, I don't enjoy being accused of min-maxing for the sake of it, so I'm not opposed to making single-classing more appealing, as long as multi-classing remains a viable option. I think that's the way to go here - make it less common by making the higher levels more interesting, more attractive. But don't take away my fun just because you don't like multiclassing as an idea, I already have to argue with my GM enough about that.
