The speed changes were another nail in the coffin of DU for me. There is no rationale to having mass-speed relationship, neither in physics nor in the game's lore or appreciable need. It could have all been handled with mass/acceleration - the "old school" way. More mass - less acceleration, less mass - more acceleration. Sure you couldn't outrun anything that's already heading in a direction at max speed, but as soon as you turned you'd gain lots of distance away from a heavy weight pursuer.
In a way, the clipped element debacle was the nerf way to go around something that could have been solved with buffs. Devs could have added more OP high-tier engines to satiate the need for speed, at the appropriate (high) cost, instead of messing with everyone's constructs even if they don't PvP. The turn rates also go nerfed for PvP reasons but affected 100% of people. This is all the examples of the wrong direction the devs took, and lets be really honest here - the only reason fast PvP ships were needed was to chase down the multi-mission haulers who weren't interested in PvP and rob them blind.