I appreciate the current format and believe the boring aspect is exacerbated. It is true that some teams were reused a lot, and there were common cores. However, it felt to me that the team who did well were the ones which were the most able to diverge from these structures and take advantage of metagame trends with out of the scope metagame picks. The teams that kept reusing the same things over and over usually tend to lose to the ones who kept innovating. WCoP is the tournament where teams have the strongest identity and where team work is the easiest, meaning working as a team on ideas isnt as hard as when you have different timezone from your teammates and you all communicate in your mother tongue (not necessarily true for every team, especially continentals, but accurate for most teams).
Nonetheless, I do understand that some players would like more variety in the tournament. However, it is hypocritical to suggest Old Gens or even just Master Gens to replace them. I feel like Soulwind made a great
post explaining why Old Gens wont make the tournament less boring (if not more).
If boredom is to combat in WCoP, then the obvious solution should be lower tiers. Lower tiers are easy to learn because they are not super optimized due to tier shifts basically reseting them every couple months, which means that the knowledge gap between a newcomer to the tier and a mainer isnt as significant as with old gens that have been roughly the same for years. Lower tiers are closer to CG OU than Old Gens, even Fairy gens. This is very obvious with SV and might continue with future generations; there isnt much in common between Master Gens and SV beside the same type chart and a couple of pokemon like Clefable and Landorus being in the tier, while the introduction and removal of mechanics, Pokemon, moves, and items make them very different tiers. On the other hand, lower tiers play very similarly from ou, with the only difference being the available Pokémon which is already a difference present between CG OU and Old Gens. I do also believe lower tiers would keep this particular teamwork atmosphere that is very unique to WCoP, as recreating / reusing teams isnt as efficient in lower tiers, and keeping being creative in the builder is rewarded.
As for the choice of lower tiers featured in WCoP, I do believe we should only keep the most accessible ones. DOU is completely isolated from the rest of the lower tier community, due to be fundamentally different from single tiers. While it is acceptable for auction tournaments to have an isolated slot, featuring it goes imo against the spirit of WCoP. This is especially true with
WCoP overlapping with important VGC tournaments, something which has been an
issue for the other DOU trophy tournament. This would leave the 6 Slam tiers that should be able to fit with 4 SV OU slots. If there needs to be less lower tiers (either because we want 5 SV OU or 8 slots), then it should be LC next due to being the least alike the other tiers format (level 5 + not being usage based). If we need to cut it to 4 slots, I'd say to remove Ubers as it is the least alike to UU, RU, NU, and PU due to it not being usage based and using a different tiering policy allowing them for more hypercentralization.
Thus the formats I suggest are:
4 OU + 1 Ubers, UU, RU, NU, PU, LC
5 OU + 1 Ubers, UU, RU, NU, PU
4 / 6 OU + 1 UU, RU, NU, PU
tldr: 8 CG OU is fine. Adding Old Gens is hypocritical and making the "problem" worse. Lower tiers should be included to add more variety, with UU, RU, NU, PU > Ubers > LC > DOU