Heh, great idea. My thoughts, some contradictory...
There are precedents for civilizing bad languages by putting syntax preprocessors in front of them.
- In the early days of Unix, Fortran was popular and about the only portable language because most machines had no C compiler. But the vanilla Fortran of the day didn't even have block structured if-then-else, just a goofy single-statement if or an if-goto. So, the Ratfor language was implemented as a preprocessor for Fortran-66.
- I believe there were (are?) Cobol preprocessors that presumably dealt with the verbosity and limitations of early Cobol dialects.
- To this day Unix-derived systems ship with a macro processor called m4.
- Several CSS preprocessors are available today, most notably Sass and LESS.
But...
- Just let it die, and the sooner the better
- The problem isn't really in the syntax.
- I don't see much of a JavaScript-PHP parallel. JavaScript is a great language. It's kind of the opposite of PHP.
- I'm not sure why you say that PHP is a great language. It's one of the worst. Every decent feature is a patch or repatch in a recent version.
- As you noted, there is a fixed-up version of PHP already: it's called Ruby and, as a language, it's near-perfect. There is another fixed-up version called Python. The world would be better off in the long run if we support the better systems.