You did RFD at level 24. 10-16 levels under most mobs in the instance. I feel bad for your group.
No you don’t need a group that’s higher level than the last boss, but you also don’t want to be going in when most mobs are skulls and will pull from several screens away…
Start your own group then. People can ask for whatever they want for their own group and you can make the requirements for the group you make. Pretty simple fix.
Healers can be the lowest level party member and have very little impact on the group. You don’t need to be a higher level than all of the bosses, but being 5 levels lower than all bosses as a tank is a PITA. Same goes for DPS. Spells start to get resisted a lot more, attacks miss and glance more often. Healers don’t really see much besides a smaller mana pool.
Graveyard is a joke. But if you can’t hit the boss in SM Cath, your level really does matter. Now you can still be a little under and hit just will be a little longer. But if you expect to get there at 34 think again.
I ask players to at least be orange to the last boss, so 4-5 levels below the final boss max.
That being said, it starts getting more difficult around RFD and Uldaman. You need a party of dps lv 44-45 at least to stand a chance against the last boss.