Long ago now, so long it feels like another lifetime or something, I built a ferrite mag alternator that worked quite well for its parts and my lack of knowledge.
I used nothing more than "upcycled" ceramic magnetron magnets on a large disk. I could get about 750 watts from it, and it was FAR from a well designed alternator.
Most of its limitation I believe came about from the undersized wire used in the windings, and not matching the load well, yet having more than enough blade. All turned to heat in the windings, which was it's fate. It didnt last more than a few weeks I believe.
It burned up when the batteries were low, and the wind was not.
This was just the initial setup to see what I could make of them.
I eventually had a flywheel on the back of this to make it sturdier.
That disk was 20" which likely helped it a lot.
Seems I cannot locate, or didn't upload any more of the pics from the project.
But yeah it most certainly can be done well with ceramics if you compensate for the lesser powered magnets.
*edit*
Going by the picture date, that was 2004.
Ouch, that's one way to make a guy feel old..