I am not sure what your plans are for the long run, but for the immediate future I’d appreciate some Hype tags like IE had back in the days (and a fixed parser!). This might just be really great…
<!--[if HYPE]>
This is rendered in the Hype GUI but will be stripped in the exports
<![endif]-->
Other solutions? Ideas? Having extended Symbol Bundles package all this would even be better (including them having a portion running on HypeDocumentLoad).