I have a couple of amusing ones, having recently got the Psychic cards myself.
- Eldar. Can summon literally their ANATHEMA, their most HATED and FEARED enemies i.e. Daemons of Slaanesh, up to and including Keeper of Secrets.... but can no longer use their mind to physically move objects (Telekinesis). So the fact that their most BASIC technology (Wraithbone) has to be psychically manipulated into different shapes and textures and forms is represented by not having access to Telekinesis. But they can summon Slaaneshi Daemons. Also, with being able to flat out ignore Perils so long as you keep a die handy... they're the best Daemonology both Sanctic and Malefic casters out there.
On the other hand, you don't have to take Malefic, so if it's a problem then just don't roll on it - I wouldn't say Daemonology is particularly strong anyway, and despite ignoring Perils it's still potentially inconvenient by reducing your Warp Charge pool. Ghosthelms do let them do some good stuff with throwing a load of dice at one pivotal power though.
Where did I miss Paladins being 4++? I've mostly just been skimming, but I didn't think they were given Iron Halos to start.....
All Grey Knight vehicles, from Land Raiders to Dreadnoughts to Stormravens to Rhinos, have Sanctuary and Banishment. 12" bubble of +1 Invulnerable Save, and with Grey Knights, you're pretty much guaranteed to get it off. Even better, it only causes a Glance on a Perils, so that's not a problem, and if your opponent shoots the vehicle instead of the Paladins, it's a. drawing fire from the Paladins, good, and b. can be protected by a DA Power Field Generator for a 3++ Land Raider or phalanx of other vehicles. Oh, Grey Knights being Battle Brothers with Dark Angels is a happy day.