This is the electric plane.
There are more ancillaries dependent on electricity than any comparable aircraft, (by a long way); It's hardly surprising that it's had it's fair share of electrical issues.
Battery and foreign objects inside distribution boards aside, how many electrical issues has the plane had? Significantly more than any other new build?
So to answer your first question, no, I don't think there's much correlation between the flight testing issues and the current issues.
Boeing made some brave choices, battery is just one of them. Jury is still out on the battery but the plane is quiet, economical and pax friendly, not sure what you mean by commercial considerations?
As a medium/large wide-body aircraft, it has to meet or exceed a multitude of criteria to be qualify as an ETOPS 180? passenger aircraft, potential carriers will quickly raise any salient issues followed by the insurance companies.
Is the implication that cost considerations are impacting on flight testing?