The "rule" about obscuring the hub with your handlebars is a good starting point, not gospel....kinda like KOPS for your foot position.

If you really want some decent pointers, you should probably give us a pic with you on the bike....on tops, hoods, and drops.

Ultimately, your comfort on the bike and control of the bike are the main objectives. If you are interested in better performance you may have to sacrifice just a bit on comfort, but not much.