I would like to bring something up about the current TLRs. It came up in IRC today when I was discussing Regigigas. As such I might be a little biased here but I'll try to limit it as much as I can.
TLR Difficulty:
Essentially, what criteria are we using for determining what dungeons deserve "Training", "Legendary", and "Uber" difficulty status? At first I thought it was just "how much this legend breaks ASB", but now I'm not so sure. The thing is, I've received word that the upcoming Darkrai and Cresselia dungeon is getting a Legendary dungeon (admittedly a really hard legendary dungeon) while Regigigas currently has an Uber dungeon. If we're basing this off of how powerful the Pokemon is, this does not really make a whole lot of sense to me, as we're comparing a Pokemon that has the most powerful sleep move in ASB (sans Spore arguably) having an "easier" dungeon than a Pokemon who's crippled with a 4 Rank Attack and 50 Speed for 5 Actions.
Enough about that comparison though, what I think really needs to be created is some kind of criteria for what gets placed in what difficulty mode. This prevents TLR creators from making dungeons that are easier or harder than they're supposed to be. To give an idea of what I mean, I'll give my own ideas for each difficulty:
Training: This tier holds any Pokemon that is unique and hard to obtain in game, but who's stats or movepool bring it below the level of many ASB threats. Examples: Floette-E, Phione
Legendary: This tier holds Pokemon that are unique and hard to obtain in game, and which also have an advantage over Pokemon in ASB, but are not especially overpowering. Examples: Three Beasts, Three Birds, majority of the "minor legends".
Uber: This tier holds Pokemon that are unique and hard to obtain in game, and which pose a significant or overpowering advantage over other Pokemon in ASB, whether due to stats or special moves. Examples: Rayquaza, Mewtwo, most "cover legends"
Uber+: Arceus, and any future Pokemon that match it's power and versatility.
This is definitely up for discussion though. There's also a bit of a grey area that I understand (Genesect for instance), but first I think we should figure out what criteria we're using before listing which legendaries go where.
Mega Stones:
Another thing that needs to be discussed more thoroughly I think is how to distribute Mega Stones and Primal Reversion items. Right now the idea seems to be to just give it away within the dungeon as an extra hard boss fight. This is fine for most cases, but I'm not sure how this will work for certain Pokemon. To give an example, let's say Gamefreak gives away a Primal Regigigas late in Generation 7, and let's assume somebody caught it at the tail end of Generation 6. Are we going to force that trainer to capture the Pokemon all over again just for the item?
Note that this only includes Mega Stones, Primal Reversions, and maybe stuff like the Gracidea. Things like the DNA Splicers and Adamant Orb can usually be distributed in that dungeon win or lose the boss fight.