so, don't expect to understand my mind 
I think that a solution to TC features that someone want to be implemented and someoneelse doesn't would be to add a new type of plugin that is tightly integrated with TC and his behaviour.
I'm thinking at a plugin interface to allow the modularization of TC.
The "multi-rename-tool" should be a plugin.
The "compare-by-content" should be a plugin.
The "directory-synchronization" should be a plugin.
SlowCopy should be an "alternative" plugin to the "standard" copy/move operation plugin.
How to do this?
1) Plugins could access standard TC "cm_" commands and provide new "cm_" commands to TC
2) TC should provide "services" to get informations about current panes prositions, current selected files, and so on.
3) TC should provide "services" to access files (because of different way it has to manage files than standard windows shell).
4) TC should provide a standard "configuration" editor for plugins or plugins provide a "configuration tab" to be integrated with TC configuration.
You should try "miranda-icq" (a lightweight opensource ICQ clone) and look at its "plugins" to better understand what I mean.