First off, I don't like the idea of giving 25 man raids better loot and uncoupling the lockouts. I think that goes too far in terms of setting 25 man raids on a pedestal. Believe it or not, what I personally want is a system where if you prefer 10 man raids, you can do them, and if you prefer 25 man raids, you can do them. It may not be possible for both raid sizes to be equally viable, but making it so you can run 10's and 25's on separate lockouts and then putting the better loot in 25's just cements 10's as the also-run raid size. Now, if you put better loot in 25's but keep the lockouts shared between them, the relative ease of organizing 10's and running them would balance that out to some extent, but I actually prefer the idea of separating the lockouts but not giving 25's better loot.
Segregation of raid sizes
Why do I feel this way? Because it makes running a particular raid size completely optional. Say your guild is a strict 10 man, you run 10's and love running 10's, but you're friends with people in a 25 and you're online when they're short a player. With a separate lockout but equivalent gear, you don't end up with the Wrath of the Lich King scenario where 10's had to be designed to be run with less players and worse gear, and you can allow people some leeway in terms of going back to raids at a different size if they want to.
Now, I'm not a fool. Well, okay, but at least I'm not foolish about this - I know that some guilds will immediately start forming 10's to farm gear twice as much, running the same raid as two or three 10 mans and a 25 man. I know this will happen even if the loot tables remain the same and only the lockouts are separate. I don't really have a problem with that. I don't mind people farming up gear faster, maybe getting some offset pieces they otherwise wouldn't get. But if you do, there's ways around it. You could make it similar to LFR, where you can run it on 10 and 25, but the first time you kill a boss in a week, that locks you to the loot that dropped that first time and any additional kills of that boss give you no reward. With the Charms of Good Fortune, you could even allow people to roll again (like in LFR) if you wanted.
The Lessons of the Past
I remember the days of Trial of the Crusader, when some raid groups found themselves running the same raid four times a week. So I understand that there are dangers to the separation of 10 and 25 man lockouts. Big guilds absolutely will have more chances at loot if you decouple the raid sizes and do nothing to prevent them from getting gear from both lockouts. Even if you just allow them to spend more Charms, you're handing larger guilds an advantage over smaller ones that just don't have the numbers to run 10's and 25's. But it's not an advantage that marginalizes by raid size, and it might be enough of an advantage to keep 25 man raiding viable. At present, we're toying with adding more loot directly to 25's just for showing up. Making it so they have to actually do something, even if it is running another raid size, might be a better option. But we do have to be careful, especially once we factor in heroic difficulty encounters. Once you break up the lockouts, you're really encouraging raids to shop around for the easiest version of the encounter and do it on that size.
In essence, I support the idea of separate lockouts as long as that idea doesn't marginalize either group. As much as I personally prefer 25's to 10's, I don't want to kill 10 mans or make them second best. You should still be able to get legendary items in 10's, still be able to get geared in 10's. What I'm hopeful for is that this is the first step towards making raid size truly optional, a choice made purely based on the preferences of the groups in question.
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