Sorry . Kind of in the dark on this. I've always thought that since the mechanicus is the main source of tech personnel then tech priests work for both imperial regiments and space marine chapters. I've read very few books on warhammer 40k but I do believe there are techpriests on space marine ships ? Or am I wrong?
Not sure about the ships one, I doubt it though. Techmarines are space marines that have gone and studied the arts/mysticism of the Mechanicus. They are still genetically engineered, power-armour clad, hulking warriors.
I could swear that Q&A had something in it about techmarines... Q) Techmarines (and other factions equivalent), what sort of machines and technology will they be able to build/use in combat? A) Brent: No promises on techmarines at launch, but expect the most iconic things to be represented- like the Thunderfire Cannon! Well hes not saying no but then again hes not saying yes either Personaly I would love to see techmarines, oh and yes your warpsmiths and warsmiths goes into this category imo.
But why would you like a technician class implemented? I am not against it, I am for it, but what would you like to see in the techmarine\warsmith, mek or a bonesinger? Let's suggest they will be able to install temporary defense turrets, both automatic and controlable with limited\unlimited ammo. What else could they do, repair vehicles, build temporary fortifications, craft in field conditions or be a buffer class? I suppose tacticals will have most of the utility abilities, but let's think what the technician's role(not a healer, obviously, that apothecaries' work)?
repairing vehicles, building turrets that are either automatic or can be manned by the techmarine, supplying ammo, perhaps you could unlock something like an improved dreadnought CC weapon, and in battle if the dread gave you enough time, you could install that weapon onto the dread for the time it was alive. edit: also, the servo harness would serve as an ability to have more weapons...