I've played a bunch of games with my Dread-bash Purifier list and I rather like the list. There are a couple observations I've made about the list both good and bad. I intend to take this list (or whatever evolution it's in when the time comes) to NOVA, so I'm pretty excited to see where the list ends up compared to what it was when it started. So what are my observations?
Things That Were Really Good
1. Psyflemen. I really can't overstate how good these have been in every game. Psycannons are often hit or miss for anti-tank, but Psyflemen are just ultra consistent. People say they are relatively fragile, and it's true, but to focus fire on them requires you to ignore the mechanized GK threats in the midfield, which is perilous too. There are no easy target priority solutions for an opponent, since most people's 48" weapons can't beat them in a war of attrition, and those weapons are what they count on to stop my Rhinos. In the games I've played, not once have all three Psyflemen been destroyed by the end of the game. There is always at least one of them alive and shooting, and in most cases, more than one.
2. Big Purifier Squads. I understand how MSU works. It like MSU. But I also like my forward units to be able to swing the game. Remember, cost is only half of the efficiency equation. Effectiveness is the other half, and it is just as important. Big Purifier squads moving into the midfield or opposing back are just super tough. They can outshoot almost anybody at short range, and while they can't dominate CC, they can hold their own. Plus they are Fearless. This is huge. When I rush a unit into your backfield objectives, you have to kill them to a man. As fragile as Space Marines supposedly are, killing a big squad of Fearless Purifiers while they are sitting in your backfield isn't the easiest task. And you must kill them, because like I said, they can shoot well and CC well. If you ignore them they will do serious damage.
3. Fortitude. If this were available as a 5 point upgrade for all Marines, they would take it in a heartbeat. It is so far superior to Extra Armor that it's not even funny. I can think of a half dozen times where a Psyfleman or Rhino embarked squad unshook themselves and then went on to do something great in the shooting phase. That is the GK difference, and it has been one of the most effective forces on the table top. If you're playing foot GK, using Interceptors and Dreadknights and Terminators, you're ignoring one of the most overpowered aspects of the codex. And ignoring it to your detriment.
4. Crowe. Yeah I know what you're thinking. In nearly every game I have reserved Crowe and when he has walked on, there has always been a scouted/infiltrated/outflanked enemy unit threatening my backfield. And in every case, he has done something great against them. Single handedly killing everything from Eldar Rangers to Blood Angel assault squads, he has been useful. And not because he is especially awesome, but rather the synergy he has with the rest of the list. My midfield and forward units are combat oriented and quite scary. My backfield is... 3 dreads with no power weapon. Crowe synergizes well in that he punishes people for extended to my backlines. If you want to push up to shut down the Psyfledreads, Crowe will be there to punish you for it.
Things That Weren't Amazing
1. Venerable Melta Dreads. These died every game, usually before they did much more than pop a Chimera or Rhino. I know the concept of earning your points back is fallacious, because these Dreads often took a ton of anti-tank shots that would have been aimed elsewhere, but my issue is in a small/elite list, I don't want a pincushion. I want effective and efficient units. Frankly, these cost too much, and do too little. Upgrading them to PsyfleVenDreads would make them extremely powerful, but the points aren't there for that in my current configuration. Mid-field melta, even if it is just a threat rather than an effective resource, is valuable, so if I cut that out of the list, it will have to be for something worthwhile.
2. Hammerhand. In many of my games, the times I needed it, it got hooded. The other times it was either overkill, or Cleansing Flame was better. In a great many scenarios, Cleansing Flame math-hammers better, even against MEQ.
So with all this in mind, I have thought about (and bounced ideas off Timmah) the changes I want to make in the list that I'll be playtesting soon. Later this week I'll post my updated list (with pictures since I am still semi-hobby oriented) and then more battle reports. Hopefully the 2.0 list is better, but if not, the 1.0 list hasn't been that bad.