Laravel is a great platform, but is there a reason this was not built like PhalconPHP as a PHP extension? I would only assume that it would skyrocket to the top of the Framework list for speed and friendliness. I like Phalcon a lot but the lack in documentation and videos just makes it really hard to understand how to get things done.
I like @virgiltu 's proposal. I'd suggest not to use C and use zephir. Extensions are 10x faster than running plain PHP, I'd actually suggest to write a transpiler for PHP which takes in PHP script, transpiles into zephir extensions, convert whatever can be done, and skip the rest.
Whatever can be converted, will be automatically used anyway, and whatever can't can get a closer look a little later from community. I'd like to see everyone's opinion on this one. Zephir's code is very close to PHP, and transpilation should also be quite easy :) (I'm no expert, but I believe it shouldn't be too much of a big task :) )