Rarely do ammeters fail. If you are blowing fuses I would look closer into your wiring. Check the wiring schematic in the operators manual, it's really very basic.
Yes, the dozers are over powered for their weight class, imho they should weigh 1,500 lbs. more.
These machines have very poor rock guards and no track shields at all (part of the low cost I assume), so you have to be careful in making turns, slot dozing, and working in mud and wet soil. They also do not have belly pans, so you have to be extra careful when working in the woods.
As an aside, could I ask your indulgence in terminology? There is no "ignition switch", it's a key switch (no ignition system on diesel engines). This will help in conferring with diesel technicians.