Dont join groups that reserve items?
Make your own groups if you have green gear and want to do something above your gear level?
Everything you think is bad can be solved by just making your own group. Except the sapming chat ofc, that part is the social part of forming the group. And you can decide what classes you want.
I mean GL doing the pre-nerfed BF HC with a green/blue geared group consisting of a Druid tank, Paladin healer, Warrior DPS, Rogue DPS and an Elemental shaman. Because that type of groups is what you will get with LFD. Sure the Dungeons in Wrath are complete jokes so tyou can do them with whatever but still.