This is a cautious suggestion from a non-pilot with quite extensive involvement in maritime CRM.
Would it be practical to give the express authority to order a go around to the PNF, in all cases?
Obviously the PF can go around at his/her discretion. No need to change that.
The PNF is looking at the same instruments and the same view out of the windows. The PNF is very much less likely to become task saturated.
If the PNF has formal authority to command a GA at her/his sole discretion then the PF, even if task saturated, is much more likely to comply instantly.