Fork editor, or create own plugins with new names?

I use CKEditor 3 with Plone 4. In our project, we need customized versions of the link and image dialogs (and some minor changes, like another set of special characters). Many adjustments can be accomplished via the Plone integration, of course.

We managed to replace the link dialog (which is used via toolbar, double click and context menu) by another one with new plugin, command and dialog names. It seems to be a little bit more difficult with the image dialog, which currently works via toolbar only; despite the original plugin should be disabled, the original dialog is activated by doubleclick.

Similar problem for the table dialog: We didn't replace it but added some customization in a javascript file:

CKEDITOR.on('dialogDefinition', function(ev) {
	var dialogName = ev.data.name;
	if (dialogName == 'table') {
		var dialogDefinition = ev.data.definition;
		var mainTab = dialogDefinition.getContents();
		dialogDefinition.minHeight = CKEDITOR.env.ie ? 375 : 345;
	}
});

This works for the toolbar button, but not for doubleclick!

Thus, my general question: Is it wise to try to tweak the original version by switching off standard plugins, replacing them with own customized versions, and do minor tweaks by such customization code -- or would it be better to fork the editor?

Will this consideration change with CKEditor 4?

Thanks for your opinion (and for any help, of course)!