Oh... I see what you want, but I guess that you really want is more fun!!!
I said that because I think that sometimes, in terms of efficiency simple ways are better. So maybe at this point I would start considering to use the postbit look instead of the legacy_postbit, or a hack that gives your users a chance to switch between them. After all, the main purpose of postbit is precisely to give more horizontal space to that area, and there it is.