As for the 747-8, the ground handling aspect should definitely be grouped with the other 747, they share commonality for ground handling equipment. Maintenance wise, it is more similar to the 787 than the 747, for check intervals, engine, wings, avionics, etc. If the 737NG and MAX are in different families, the 747-8 should be the same.
Also, I think the A320ceo and a320neo family should have a special thing. They share 95% same spares and parts, but since there is a new engine, there is a separate competency. But it is only ~0.5-1 day more of training in addition to the A320ceo training. So maybe they should be grouped but somehow different to account for additional 0.5 days of training and the 5% part difference and new engines.
Also, I think the A320ceo and a320neo family should have a special thing. They share 95% same spares and parts, but since there is a new engine, there is a separate competency. But it is only ~0.5-1 day more of training in addition to the A320ceo training. So maybe they should be grouped but somehow different to account for additional 0.5 days of training and the 5% part difference and new engines.