Jermiah,

The edges of the range tend to be notes that require a bit of work--you use the word "useable" and that tells me that the notes are there, but you have some other problem(often, for the low notes, it is too much air, not enough sound)--there are a lot of little tricks to getting those notes out, and those of us who seem to have been given the "gift" of a wide vocal range really have done a lot of work on the edges.

Roger,

When you turned forty, you became entitled to do what you want, and if people don't like it, that is their problem-- I have been doing research into English Common Law, and it turns out that you have a fundamental right to sing, no matter what it sounds like.

Anyway, your voice is ready, you've just got to figure out how to get it to do what you want.