Well I had a different experience with the WoW holidays because it had content for all the players. It was more in depth and had stuff you could do solo and stuff you could do as a group. What killed the boss fight in for some was the Dungeon Finder because of what the DF is. Personally I had some good experiences even using the DF because I ran into some cool peeps but I know how that goes I could have just as likely ran into pure elitist pricks.
You are actually comparing the two games wholly and I am not I am speaking only of all holiday events and how they bring more content than not. I want to see all classes and players to be able to join in and have fun whether it via solo holiday content or it be with a group, also I would like to depend on the DoL/H to be a part of the event. That would make it feel alot more FFXIV like. With more content that wouldn't make it any less lighthearted it would just please more people.
I just want more content for holiday events that utilize solo play and group content. I would like to see more mini games and even some quests added that add more meaning behind the events that are going on and that add more lore to Eorzea. If I ran this holiday event I would have made it similar but added stuff for DoH/L to do and would have added a bomb NM to fight and the DoH/L could do emotes at it during the fight to anger the mob and make him go berserk for a short time. Then the DD could go nuts and burn the mob down and it may take 2-3 berserk phases for you to drop him depending on the amount of ppl doing the event. This bomb would drop some special loot and materials for making the best swim suits. Maybe the loot would be fireworks or other odds and ends that all players who helped during the fight would receive by talking to an NPC. Just by adding more content could the event really blossom into something it currently is not. Maybe the design team don't want to put that much effort into it but I really do want to hear from them for future content relating to holidays if any they have in store for us. Also this wouldn't be all the events done this way just certain ones, you would still have half or more of your events done in the normal way they are done now.