Can I ask what's wrong with the Canon A510? I don't know anything about that model so you'll have to expand on why you think you need a "higher end digital".
I posted a thread in the ViewFinder forum and many people have responded to it. Take a look if you haven't already. Maybe it'll answer your question. If not, let us know.
As for accidentally deleting files, as long as you regularly download files to your computer, you won't risk losing any more images than you would by accidentally opening the back of a film camera.