Gibson SG bass neck dive solved with Hipshot ultralites. This is my go to bass, light, balanced, short scale. It is not perfect, the E string lacks a little something compared to my long scale basses. Chowny SWB-1 neck dive 95% sorted with some s/h BC Hipshots from a Cort. Strangely (in view of the Physics) the Chowny balances better with a strap-lock fitted to one of the neck bolts rather than the top horn. @Andyjr1515 has all the right answers (from my perspective as an ageing Physicist) on why short scale neck dive happens.
Here's something I built a while back, 32" scale length. Absolutely no neck dive, 7.9 Lb and no Hipshots ... read on
Anti dive provided by a 1 Lb block of lead at the bridge end and Retrovibe machine heads - a few g more than ultralites, way cheaper and just as good imo. Moments about pivots again. The parallel neck shape was an experiment following a 3 string CBG build. Not to be repeated.