I don't see why TM couldn't be improved to support other, AST-based parsers. Sure TM is lacking now but we cna fix that. I don't think it's too much work.
But coming back to this PR. I don't think the proposed query API is affected by the above ideas. It'll always be used to return a list of tags. If the TMTag structure changes for new features or are subtrees instead of plain tags is a different story.
So, what needs to be done to get this merged? @b4n @techee @codebrainz ?