Keynote: export tiff and create JPG to same location all the time?

Lately I’ve been making Keynote presentations to export as slides to import into iMovie projects. I always export as tiff, and I always need to make the first slide into a JPG to upload as a preview thumbnail.

What I’d like to know is the best option for saving the “Export, as Tiff, to Desktop” steps and shortening that. Would it be Keyboard Maestro? Or something in BTT? Or am I better off using Default Folder (I don’t think it can do that automation)? I think the hangup is going to be converting that tiff to a JPG (or maybe it should be a JPG the whole time?)

Thanks for any help here; I appreciate it.