Another reason to give SW dreads a long, hard look is that SW get access to Venerable Dreads with Great Axe and Blizzard Shield. Giving a likely shooting magnet a 4++ is really, really nice. Also, the adaptability of the Great Axe's two modes allows the model to face any combat situation and have a weapon that is going to do the job that it needs to. Last OFCC my Venerable Dread with Great Axe and Shield was hands down one of my MVPs, pulling its weight and making up its points spectacularly every game. If you want to build an all Dread List consider just taking a bunch of Iron Priests (SW) or Tech Marines to heal up your dreadnoughts as they take damage. SW also have a handy strategem that allows you to pick a dreadnaught and everyone within 6" can reroll 1s to hit for the phase. Acute Senses (another Strat) allows a model to ignore negative to hit modifiers in the shooting phase. I used it last year a lot on my Redemptor Dread to allow it to move and still fire its Plasma Cannon Thingy (yes that's its name!) at full BS. Definitely some fun stuff that SW can bring to an all dread army.