I don’t think DE routinely published change logs. Supposedly, when the major version changes, that means there was an OS change (not necessarily game rules). Other than that you generally have to figure it out on your own. It is true that the latest version is not always unequivocally the best.

It’s possible that a new bug, rule change you don’t like, or removed feature might have been introduced in the last revision. For instance, Rocky and Bullwinkle has a version 1.30 and a version 3.20 out in the wild, but Data East / Sega / Stern always said 1.30 was the “latest” in their official publications. Doesn’t really matter for home use, but I think 3.20 has a broken coin pricing setting and instant info may report an incorrect number of extra balls under certain circumstances.

Although not a Data East game, as another example I’ve read the last RBION ROM doesn’t have the “Go Backwards” award that was previously available in some modes (and I run an earlier version in mine).