fgrieu,
The runway trim situation could still be a problem, as you indicate re ET302.
My reading between the lines and from collated opinion, the combined software modifications and monitoring, stick base cutout switch, and a revised (clarified) procedure with refresher crew training, might balance the probability of malfunction - providing no MCAS failures. Even so this depends on human performance to shut the trim off before excessive trim forces would be encountered; perhaps with a big red light identifying trim runaway - but that would be challenging engineering task, dual FGCs at all times …
The training requirement could also apply to the NG, and previous variants.