This is the exact request I'd make, for the same reasons. The more we take advantage of themes, the more of an urgent ask this is.
Sorry about that, that has not changed, however the developers did make it so that if you were on songs, and go to themes it will always load song themes, if you were on scriptures and go to themes it will load scripture themes and so on for Presentations. This is to accommodate the compose function that allows you to click on a song, a theme and go live. I'll take the implemented off of this, since it did not get implemented exactly as requested.