Medusa and light needlers are an interesting topic. The short of it in my eyes is that light needlers pair extremely well with the Medusa's capacity for strike attacks and also does better than the railgun for flux efficiency in a prolonged fight, but also pair very poorly with the Medusa AI's phase skimmer (We love using up all our soft flux to shoot light needlers, only to cancel the light needler shots with a phase skim!) and can be prone to being armor tanked depending on your other weapons. I think this means railguns or light needlers are both good on Medusa and their individual weaknesses mean it's probably about the same end result? Then there's also the idea of PD Elite boosted machine guns in those slots, All really cool to think about. And past that, there's the idea of using kinetic fragments or mass drivers, hehe.
Focusing on the OP topic, mirroring Bungee Man's thoughts, we have a lot of builds that can win against every enemy you can fight against, not just lowtech kinetics with PD. I don't think that's necessarily a bad thing. It depends on how easy the build was to create, how many resources (officers, smods, unique/notable ships like Onslaught MK1, player skills, etc) it needed and the like.