I don't know if this has been suggested before - quick search didn't bring up anything.
What if we were to change the Shadow key price to 450CE but make it per person? I say this because it would make it a lot easier for people who like solo play or have a small group of friends playing this game to get into doing shadow lairs. It would also make it slightly less scary to do with randoms.
I fit into this category of player and I'm sure a lot of other players do too.
I know what your thinking though "but what about all those shadow keys already out there." Well just split them in 4 with the update. (4 * 450CE = 1800CE).
It also shouldn't affect any profit making either because anybody making a profit off these levels are already paying 450CE per player when they get together in groups anyway.
I haven't played a Shadow Lair yet, so I don't know their payout
(would their loot have to be lowered since there'd be more players soloing Shadow Lairs?)
If this happened: Players with old Shadow Keys ought to receive x4 keys for every unused one they have.