I strongly prefer smaller parties. Especially in pen-and-paper, but also in video games. More characters makes everything more complicated and unwieldy. It makes everything take longer. It increases the amount of boring logistics you have to deal with. It reduces the amount of spotlight that each character gets. It reduces the importance of each character's individual contribution. As a DM, it's just harder to run the game for more players instead of fewer. You have to cater to more people, come up with more special things for each party member. As a player, more players means you get less time to actually do anything, and more time spent sitting there waiting for your turn to act or speak. In a video game, more characters means more inventories to manage, more gear shuffling and equipment upgrading and stuff to constantly have to deal with. It means characters getting in each other's way more often, a bigger crowd of people not fitting into narrow spaces, etc. To me, bigger party size almost never makes the game better, in either tabletop or video games.
