Build Tips for Techmarine
I went with the top / right sections (awakening bonus, aegis bonus and the extra servitor). I try to take these servitors: (in priority order) melta, bolter and hydraulic.
I treat the tech marine as fire support to augment other knights.
I find the plasma servitor is situational and best used to push enemies into position / off ledges, but becomes less useful later in the game.