That's an interesting and
totally nonstandard way of using that field.

Since you're the only person on the planet doing it, I'd say you're better off asking Empeg when they're going to support ID3v2 tags.
Me, I just make sure to carefully abbreviate titles that exceed 30 characters. One thing you should know is that the Empeg's display can't always show the full length of a long title anyway (at least not without scrolling), even if it's only 30 characters long. So getting the extra-long titles in there wouldn't have a major benefit.
--
Tony Fabris -- Empeg #144 --
Caution: Do not look into laser with remaining good eye.