Here is some news from Blizzard Poster Tigole in regards to the next patch and some Instance changes:

In the 1.6.0 Patch (Blackwing Lair patch) there will be some pretty significant changes made to the spawn density of Scholomance. It should be much quicker to clear than it currently is. Also, we added a Graveyard to Caer Darrow so if you die, you're much closer to your corpse.

We also made some more adjustments to Stratholme that will go live in the 1.6.0 patch. We made some of the pulls in the Scarlet side easier to handle with 5 man groups. We also put the Ghouls in the guantlet on the normal respawn time (2 hour) and reduced the overall number of Gargoyles. We think we fixed the In Combat bug with the Ziggurauts as well.

Lastly, if you fail to Rivendare or Ramstein, you'll be able to try again -- the back gate and doors to the Slaughterhouse will open.

Our goal is to have these dungeons playing as fun as possible for 5 man groups.