In principle, I think CGI::Simple is a good idea; I don't think that the module CGI is cluttered by unnecessary functions (I've used most of it, and it was all necessary), but I'll go blind if I read the source. I'm not sure about its performance issues, having always worked with it - I expect raw HTML generation would be faster.

But if CGI::Simple takes out the HTML generation methods, I won't be switching. I really hate embedding HTML; the Camel's claim that perl "makes different things look different" is all very well, but embedding HTML makes code so ugly. I think CGI.pm's interface has such a distinctive style that it would obscure the code to manually generate HTML. Oh, and where's the data on the methods not being used by "a significant percentage of users"? Most scripts I've seen use them.