are there any other ships planned that use these mounts, besides Aurora? like Medusa... putting two Light Needlers on that already very powerful ship always kinda felt like cheating. ^^
Not to me. Medusa does not need that kind of nerf. It will certainly kill the Needler and Phase Beam combo. Needlers and Heavy Blaster is too hard to support without removing Hardened Subsystems or other must-have hullmod. (I use railguns if I mount heavy blasters.) Also, two light needlers is less ballistics than the what Enforcer and Hammerhead can bring. Moving within weapons range of most ships in a fragile ship (more so than Sunder)... Medusa needs to be powerful.
I thought about it for the Medusa, yeah. Might eventually replace those w/ "synergy", heavy emphasis on "might". The range on that light needler is just so good, combined with a high-tech ship's mobility. I wonder how much the Medusa's stock would tumble if those were replaced w/ "synergy".
To answer the question, I do not think Medusa would be much less effective (because dual Heavy Blasters are so good, just annoyingly short-ranged) but it would reduce the number of top-tier configurations available. All of my Medusa would use the same one, maybe two, configurations instead of three or four.
If hardpoints became synergy, I would abandon Phase Lance on Medusa since it cannot back them up with attacks that deal hard flux (aside from IR Pulse Laser with only 500 range - too short). Unless the new ion weapons are Templar overpowered, I would use either Pulse Laser or Heavy Blasters exclusively for medium mounts, depending on skills. In the hardpoints that become synergy, I would probably use one among the following: Tactical Laser to prevent AI from lowering shields at 600+ range, Salamander or Ion Cannon for disabling, Reapers for alpha strike, or single Harpoon/Sabot for no OP cost.
Currently, I sometimes use Phase Lance on Medusa if I have Advanced Optics hullmod and Needlers to spare. If neither are available, Phase Lance gets dropped because it is overshadowed by Pulse Laser or Heavy Blaster (same range, but does hard flux).