In my recently "Tamarized" post, You're so 133t, You're Simply Irresistable (Tamarind linked/recommended it) I mentioned gear inflation, and the importance of it was pointed out even more in the comments I received (Thanks Shintar & masith!)
Bascially, the reality as it is now, is that for any given expansion/patch level of dungeon, there is enough gear available inside for everyone to slightly out gear it. Especially once the dungeon gets slightly nerfed. And the problem only gets worse once a given set of raids is superceded by a newer release.
And still, there's a need to keep gear (and the ensuing raids) accessible to the ravening
And release newer, tougher instances.
And provide newer shinier loot for each instance.
And prevent instances from getting too easy.
Um, I'm glad I'm not Blizzard. From what I can see, at least on the surface, it's impossible.
On the one hand,
If the raids are tuned (and stay tuned) for high end raiders, with the bare minimum of available loot (to prevent the dropped gear from overpowering the instance)
AND the followup instances are kept only *slightly* more difficult, and with a similarly "sparse" loot table.
AND the gear progression between the instances is kept low/small/whatever. (basically, instance one drops i290 gear, the next drops i293, and the next drops i296)
Then the older instances will still have a fair amount of challenge for the players.
Except for 2 things:
We have been trained by Blizzard to lust for gear, and the increased power it
gives us. If gear really isn't much of an upgrade, how interested will folks be
in the quest to get it? (conversely, if instances are tough enough, then even
small upgrades will be sought)
While nice for the top end raiders, the
above scenario will basically be a return to Vanilla WoW, and 90-95% of players
won't have access to the content, because the "middle" (average) players simply
can't won't be able to play at the level needed to succeed or make any
progression.
Another option
This is similar to what we have now, with hardmodes as well as the slow(?) steady nerfing of the instances so that over time the instances become more accessible.
BUT, you maintain the gear "sparcity" (or just very small gear bonuses/increases)
The problem here is that with nerfing, eventually the raids get "too easy" for the top tier players. Especially if the nerfing gets to the point that even hardmodes become readily accessible.
Now, I DO have a couple suggestions...
1 - keep hardmodes and heroics hard, BUT DON'T GIVE BETTER LOOT FOR THEM. I think the 10 vs 25 man equalization Blizzard has done is a great step in this line of reasoning. If people are truly serious in that what they really want challenging instances, well, tune the dungeon such that normal mode gear is sufficient for a good team to complete hard modes, but will make it hard enough that "the unwashed masses" won't.
This will help prevent gear inflation since there won't be extra (half) tiers of gear. Also, without the lure of better gear, "normal" folks won't feel obligated to run them, and they won't cry (as much) for nerfs.
A slight downside is that "good" players/guilds will be able to finish the normal modes without getting much (if any) of the new tier gear. But, assuming the hardmode is the "feather in the cap", then that should be fine.
2 - Realize that no matter how much folks want to avoid it, gear inflation WILL happen. If new content needs to be tougher than the old, (which usually necessitates newer, higher level gear) then it's bound to happen. Especially when multiple new raids get released. Even if Blizzard had made the difficulty jumps between raids smaller (ie, Ulduar was a smaller increase over Naxx, etc) it would still be a given that, once you had completed ICC, you would completely outgear Naxx.
3 - Realize that there will be content that not everyone sees, BUT ONLY HARDMODES/HEROICS. If the gear that drops between normal & hardmode, between regular & heroic are the same, then this should be fine.
If all of those are done, then I think that the difficulty of the various instances will still be fair/moderate, even at the end of the Cata expansion.
BUT, there is still a downside.
In general, the "progression" characters make as they gear up (currently) is something like this:
Quest blues/greens
Regular 5 man
Heroic 5 man
10 man regular
25 man regular
Heroics (10 or 25, depending)
If we followed my suggestions, it would be a *little* different...
5 man
10/25 man
10/25 man Heroic
Is that a good thing? I don't know, but I honestly think it could keep "most" players "mostly happy". Hey, this is a massive group of people, and it is impossible to keep everyone happy.
I would guess the top end raiders wouldn't like the "normal Joes" getting the same loot with less work, but I would also guess that the "normal Joes" would be somewhat unhappy that there would be content that they would likely never get to.
Then again, hardmodes/heroics are generally very VERY similar, with maybe one or two slightly different fight mechanics, with the vast majority of difference being how hard things hit. It's not like completely missing content, just not getting smashed as hard.
Are there other options? Yeah, but I'm not sure they could accoomodate the vast number of often contrary requirements that players put onto the game.