Too many gameplay restrictions

[Voltyblast]

This is a bad idea as it makes balancing things a lot more difficult. You couldn't have mechanics such as Enumeration if the party size is very variable and it limits the creativity of the designers a lot. It also limits the competitiveness of the raids as it would always favor teams with X players over Y.

Honestly, I don't agree with that, because they actually made some neat mechanics for 24 man raids: the recent weeping city has Ozma with very well made mechanics, then we had cerberus in WoD which is still an amazing boss in my opinion. Then we have other bosses like Bone dragon in CT which was very intuitive, because it required less of "OMG DPS HARDER!" and instead needed more team work and actual "crowd control". There is barely any real CC or kiting required in this game: the last fight I recall something like that was T7 and even then it all boiled down to "OMG DPS HARDER OR WE WIPE".

The excuse of "Well it's harder to balance" it's old: if anything making a 24 man raid more common would actually be more open to new strategies and would actually encourage more people to raid, as 8 man doesn't allow more than 1 class/job/whatever per group, heavily decreasing the chance for someone to find a raid. Although there's one other major trouble with that: the alliance system is broken as hell and, for example, it won't allow group A to heal group B with aoes and whatnot, making each Alliance separated and on their own. If they ever fix that (they won't), then we would have some nice raiding possibilities.

All I'm saying, there is potential and a lot of ideas, a lot more if you just consider that the 24 raids, while much easier, have some of the best mechanics ever created.
Strangely, the 8 man raids feel lacking in comparison, as it it boils down to "do this 100% correctly or you wipe". But that's just me.