After reading the Eisenhorn books, Emperor's Mercy and starting in on the Ravenor books, I have to say they need to make Inquisitors effective ICs. I have been liking them quite a bit in my army for the Psychic hood but why do their units have to blow so severely. The Acolyte, Penitent, Warrior and especially the Sage are just weaksauce in the extreme. The Acolyte is supposed to be an Inquisitor in training and he does nothing but take a shot for his boss or try some random fruitiness with a Mancatcher. The Penitent has a great save but come on lets throw in some abilities that you can buy. Having Distaff Penitents would be awesome. The Warrior is just paltry. In the books these dudes dominate even CSMs, they should at least have different archetypes like sniper, CCers(Deathcult Assassins), and Vet Guard(Marbo). The Sage is really the worst. What does having a Sage have to do with your BS? They should at least give an Inquisitor access to some new abilities or something.
Granted, I did like having an Inquisitor in a Land Raider for my last 1850 game even though it was insanely expensive and the Hood was awesome for me. But man they need to bring them in line with other ICs and the ass kicking we all know they should be doing.