Do the modules have to be used in pairs, equal parts on each side? We want asymmetry!

At the moment, all modules are 'twofers' that give you both the left and right slot, which maintains symmetry. Remember that asymmetry makes balancing thrusters significantly more difficult, so the ship has been intentionally designed to 'pair' modules in this fashion. (It's possible in the future that disparate 1x1 modules might be made available, but this is likely something we would wait until the game launches to create so that players can see them in action with the impact they'll have on the ship before choosing to buy them.)