Interesting question. But I am not sure this is the best path here.
One one of my sites I have a "gallery" page that shows a set of albums. I paginate and and present these with the JAIL loader system and the color box jQuery script.
I can also present a single Galley driven album on any page I like. What I did is create a chunk called galleryInsert that looks like this:
<div id="galleryBox">
[[Gallery? &album=`[[*galleryInsertTV]]` &toPlaceholder=`Gallery` &useCss=`0` &containerTpl=`GalleryAlbumTpl` &thumbWidth=`80` &thumbHeight=`80` &thumbTpl=`GalItemThumb` &imageWidth=`1000` &imageHeight=`800`]]
[[+Gallery]]
</div>
I then just drop the chunk name where I want the gallery album to appear on the front end page. Of course I use the Manager>Components>Gallery>Create Album path to create the album and upload my images first. Inside that chunk I have a TV that lets me add the album number. So when creating the page I add the chunk name and then enter the album number in the Template Variables pane. Once set up this is super easy to add and manage gallery albums wherever I want them. Its just three mouse clicks really.
Bottom line here: all these RTE (like TinyMCE) systems are a pain. They are flaky, often mess with your code and cause issues when upgrading MODx or the actual TinyMCE plugin itself. I think it best to not add any extra heavy lifting to TinyMCE but rather make MODX do all the work.
My $.02 anyway...
