1a. What are your thoughts about the article above?
Huge scale fights are generally epic.
1b. Does # of players in a raid or battle matter in MMO’s?
Absolutely. I do think there’s a time and place for forces of all sizes. The biggest drawback I can think of is performance. Generally, when stacking that many players into a small area, frame rate drop is a big issue. If I drop down to 5 FPS, that’s not fun, and it’s too many players/effects.
I think a limit to the number of players in a raid is mandatory. Tuning an encounter would be impossible to do if the players could bring as many friends/boxes as they wanted. “Oh hey, this is a hard fight, let’s bring 2,000 people. Sure the first 1,500 will die horribly, but they’re just cannon fodder.”
1c. What is excessive?
For PvE/raiding, I feel like the sweet spot is somewhere around 50. The biggest things for me are performance, and tuning. WoW tried to make the tuning a non-issue by making every raid boss scale based on your group size. Two problems arose. 1) there were hidden “breakpoints” in the group sizes since the scaling wasn’t perfectly individualized. 2) They fixed the scaling so it was equal based on number of players, but there was a flaw. Every encounter was designed to only need 2 tanks, so fights became easy/trivial when you would overload on dps players, as the % of tanks/healers in your raid (the low dps players), would drop. Some groups would overpower many mechanics, or flat-out kill the bosses before the mechanics came into play.
For PvP, I think the main issues are performance, and how ranged attacks/spells function. I primarily play melee/tank classes. In larger scale battles (40+), I find myself being controlled/killed before I even get into range with my opponents. Maybe a few mobility skills would allow better gap closing? I think that would be hard to balance though.