I wasn't aware of this. This looks like a bad design choice indeed. I hate when libraries convert stuff implicitly for you. html5's localStorage has a similar problem. Only, it converts whatever you are trying to store into a string. Would be better if it accepted only strings and threw an error if you tried to store something else, imho.
I don't understand this fixation on js either. Even more, i don't understand the fixation on html, css and all so called web technologies. Common, web was never designed for the sort of applications we are trying to make it run. We need a totally new approach.
I find metaclasses philosophically unsound. If one introduces metaclasses, what about meta-metaclasses, meta-meta-metaclasses. In this regard Self's prototypical oop seems more coherent - there are only objects. Even object/class duality looks philosophically more attractive than object/class/metaclass trio.
If I'm not mistaken the authors of Smalltalk realized that metaclasses were a mistake long before they appeared in Python. Yet they were added to Python anyway.
php is not unique in having big memory footprint. AFAIC Python and Ruby are also memory hogs. An interesting question is how memory efficient a dynamic PL can be. Given that in modern computers memory access (cache misses) is fairly expensive it probably makes sense to trade instructions for memory.