To the OP...I don't know if it's actually been stated here and I missed it
or just has not yet come up, but one reason for losing the bearing cages
is that you can usually fit in one or two more bearings in your assembly.

This makes the support points of the bearings and races both a little more
numerous and a little closer together, which, if you think about it, probably
improves their load performance marginally. Anyway, that's why I usually do
it, particularly in headsets.

+1 on the Grade #25 Chrome Steel balls being all anyone will ever need on
a bike, performance wise, and the advisability of replacing them if there
is any question with regard to their status. Most bearing assemblies
are consciously designed with the idea that the bearings will be replaced
a few times during service life. The races in the good ones are hardened
and will go for a long time if serviced and lubricated.

XXXMart bikes are and exception to this rule, and would probably benefit
from the aforementioned bronze bushings.