Here's a link to my current type 4 pool (286 cards):
http://www.moonkhan.org/mtg/current_type4.txtI should finish the stack sometime soon (missing Forcefield, Illusionary Mask, Timmy, Johnny, and some other rares). All in all the power level feels high. We don't use firebreather's but we're using Myojin of Night's Reach and Cabal Conditioning.
Aside from the usual suspects here are some cards we consider powerful in my play group:
Tatsumasa, the Dragon's Fang is hot.
Armistice is a great political enchantment. It's one of my personal favorites.
Reweave is powerful. It turns cool enchantments like Dawn of the Dead into cooler enchantments like Holistic Wisdom! It's also a great way to resolve game_winning_critter when you arrange your library with Flash of Insight, Aladdin's Lamp, Soothsaying, etc. It can also remove indestructibles.
With the current wave of indestructibles (myojins, DSC, Konda) Innocent Blood and Second Thoughts have proven very useful. I consider Second Thoughts a very high pick overall.
Re: Headstone - great call! It's going in as soon as I find one ... Graveyard removal is key. I'm looking for other cantrips like that because I don't want to put in Withered Wretch.
Cards that aren't making the grade:
Crater Hellion - morph-killer but that's about it
Disturbed Burial - Sorcery, too slow
Godo, Bandit Warlord - cool with Vigilance creatures but the only Equipment we use is Tatsumasa
Jugan, the Rising Star - being a cool-looking dragon isn't enough to make it into a type 4 pool
Kodama of the North Tree - sadly he hasn't proven to be strong enough to waste a main phase casting
Kuro, Pitlord - why when Smokespew does more for less?
Living Death - really this and Twilight's Call are just a way to punish Phage and it takes a lot of luck to set up. Still a fun card.
Mindblaze - when I read Kaboom! I decided that a main phase is better spent blasting everyone instead of one person for 8.
Night Dealings - I saw someone on TMD with this and thought I'd try it. No one liked it.
Reverse the Sands - ok, ok, so I thought it might be fun!
Thanks for the great card ideas everyone!
--Paul