Just in case I've missed something, we'll only ever be able to ressurect Mortek Guard and the Deathriders yeah? No other units have models with a wounds characteristic of 3 or less?
What about a world where you're Bloodtoofs and you want your cabbage to have a real artefact?
In my mind he serves the same role as the weirdnob (using a clutch hand of gork) and is also handy in a scrap.
You don't get a choice. It only summons Brimstones.
Page 127 – Ogroid Thaumaturge, Fireblast Change the last sentence to: ‘After the damage has been inflicted, you can set up 1 unit of Brimstone Horrors within 1" of the target; the number of models set up in the new unit is equal to the number of mortal wounds inflicted.’