hooks – How to enhance a self developed plugin by its own plugin architecture

The idea is to create a very basic plugin for wordpress and enhance it with internal modules and some more plugins (e-plugins) if activated.
This base plugin would have all the basic code of a wordpress plugin to work, and should load the modules and then the e-plugins if activated.
The concept (very simplified here) I have is, to do this with an enhancement class/interface, to register all modules and plugins that will extend the base plugin. Then this base plugin can use all the functionality that will be implemented by the modules and all activated e-plugins.
The advantage of this concept is that functionality that was formerly implemented in an e-plugin could easily integrated in major releases of the base plugin in just adding this e-plugin as a an internal module.

I have 2 questions:

  1. I don’t want to reinvent the wheel, so does anyone know an already
    existing concept/framework/starting point for my described concept?
  2. The standard approach is to do enhancement of plugins with action
    and filter hooks. But this has its limitations. So should a
    WordPress plugin always and anyway be extended with hooks?

Thank’s in advance

Tom