I've recently looked into 10-man vs 25-man raids and peoples opinions regarding them. It's by no means scientific but I've heard quite a few people state they enjoy 10-man raids much more than 25-man raids. I'm wondering exactly how much enjoyment is correlated to progression. I've stated before that everyone wants overcomeable challenge. I propose that people who enjoy 10-man raids more than 25-man raids enjoy them because they're easier.
10-man raids are tuned for a lower level of gear than 25-man raids. A group with solid 25-man Naxx gear will have a significantly easier time running 10-man Ulduar than running 25-man Ulduar. I wonder if the point of overcomeable for a lot of guilds is more the Ulduar-10 level than the Ulduar-25 level. While my guild didn't experience this much, I can definitely envision some bosses in Ulduar being almost impossible to kill with a weak guild. I have horrible visions of 20-minute Mimiron attempts, wipe after wipe in the arena or the tunnel on Thorim, three distinct add packs in Freya... All kinds of horrible possibilities.
So, my thoughts on this are two-fold. One, it's in Blizzard's best interest to make the game as fun as possible in order to generate as many sales as possible and as much continuing business as possible. To that end, is it better for WoW as a whole to balance down to the 10-man level? I can see arguments going both ways. Hardcore raiders have few enough challenges as-is, making the game even easier would be a terrible thing (from their perspective). Casual players make up the vast majority of WoW, but having something to shoot for, knowing that there exist a set of players that aren't casual, gives casual players some dream of progression. I'm not qualified to talk about that sort of thing.
More importantly though, why do 10 and 25 man raids have to be separate difficulties? Why can't 10 provide the same reward with the same difficulty level but just be smaller? The current argument goes something like, "If 10 and 25-man raids offered the same rewards, no one would do 25-man raids." This means that there's some inherent reason that people prefer 10-mans over 25-mans. The ease of 'coordinating' a 10-man raid vs a 25-man raid is generally the huge difference people point out but I don't buy that at all. Personally I feel like if you bumped the rewards from 10-man up the same level as 25, 25-man raiding would die out. But if you bumped both the reward and the difficulty of 10-man raids up to that of 25-man raids then you'd see about the same representation you see right now.
This is largely academic. Even if Blizzard wanted to try putting 10 and 25 on the same level they simply can't until the next expansion without totally borking either the 10 or 25 progression path- aka 10 tuned to the 25m difficulty level and requiring higher tier gear sets or 25 granting no upgrade from one tier to the next. Personally, I find 10-man raids more fun simply because I enjoy learning hard content but I don't enjoy wiping to retards. I can field 15 intelligent players, but 25 is just too much of a stretch.