+1 on stiffer soles, even if you're not ready for clipless yet.
Someone posted a beautiful pair of shoes a while back from a company that still sells cleats for toe clips (!). Unfortunately I can't remember the details, but maybe a search of the forum. Your options will be pretty limited if you don't go clipless, just because the cleats are so hard to find.
Another thought, if they're laced shoes, how tight are you lacing them over the instep? Or are you tightening your toe straps extra tight to compensate for not having cleats?
Speed comes from what you put behind you. - Judi Ketteler