Newbie Question, hard ferromagnetic core in electromagnets?

[NeoRules]

I know hard fer-rites (magnets) have less of a pull than ND magnets.
cost not withstanding would a hard ferromagnetic core in an electromagnet allow for an increase of flux when current is passed through the coil (in the correct direction to enhance the field) or would the current have to be so high that the ferromagnetic core would not produce more magnetism than a standard laminated or insulated powdered iron core?

If the current increases the magnetic field (to a reasonable degree) would that in turn overheat the magnet and possibly cause it to become less effective?

I am learning but I have searched for Jacks Magnetic Valve Principle and a few other key words and it always brings me back to a post that indicates this has been discussed several times but I can't find those posts :-P

I also discovered that using a flat aluminum disc instead of fiberglass to make a printed circuit motor on might be counter productive... (insulated of course)

Thanks JC