Do you feel that
(a) you need more variety of tags, or that
(b) the 24x80 representation of the existing tags is suboptimal, or that
(c) the task is impossible by its nature -- you must rewritethe document.
If (a), we should take that into account for HTML extentions.
If (b), you can change the DefaultStyles.c built-in style sheet
If (c), I agree. In principle. But In practice we need to comprompize.