I really, really want to add support for plugins/extensions to support custom data visualizers, but it still needs a bit of work on the web client side, mainly some code cleanup and some new ui functionality, and possibly a bit of work on the server side for easier message receiving. I'll definitely add the plugin functionality for the next version. You can send me a pm/email to discuss it further, so that I'll have a better idea on what kind of functionality you need for your custom visualizers.
Yes, but a Unity3D plugin has to be written to use the C++ server in Unity, or the server has to be rewritten in C#. Unfortunately I don't have the unity license which allows to use plugins, so I'm not going to write it, but perhaps somebody here would be willing to do it? I can provide help if that's necessary.
I could hook new and delete, and perhaps some other core functions, but I would rather keep the server code minimal and conflict free, so it could be an option which you have to manually enable with a define.
The gamedevwebtools::core::memory::Allocator is used internally to provide dynamic memory allocation for the server. I like the idea of setMallocCallback, setFreeCallback and the Service::malloc and free functions as they can provide an easy collection of memory stats. I'll probably add them to the next version.
Your object binding system is pretty interesting. I was thinking of adding just service method callback on certain message types, with some sort of internal mapping to map the types to the service methods. But I'll see if I can use a more powerful system.