In reply to Trevor Nelmes.

Thanks for trying Trevor. Alas, we've run into similar attitude when trying to help improve core (for example running multisite in a directory).

Dependencies are extremely trying. With our video player FV Player we are highly dependent on jQuery. It's amazing how many plugins break even jQuery by reloading their own version (we count on the latest version, which comes loaded by default in Wordpress itself). I can only imagine how hard it is to get clean performance when reusing parts of other people's plugins within your own plugin.

Conflict resolution (naming conventions) should be built into these bits and pieces so you can't end up fighting over data.

It sounds like the namespaces solution is the only safe one. We'll all be on PHP 7 very soon, so requiring PHP 5.3+ seems okay to me.