have now ridden both a 6’2 blackbird and 6’1 ghost, both stock dims. only one (really good) session on the ghost but a few things stood out switching from the blackbird on HH+ days -
for general board duties, blackbird is more an all arounder and ghost is for ripping.
BB is stiffer, better in chop, and less paddle form required in the deathzone/soup. It kind of damps things out which is welcomed in rougher seas but that leaves you wanting more performance on a clean day or the right wave.
for san diego and one board only, I’d lean towards the blackbird as it would get more use. But, when conditions are right, way more fun will be had on a ghost. the ghost really does feel longer than it is so I wouldn’t go any longer than my height for socal. blackbird rides true to its length and could easily scale it up 6-12” without much thought. Sized at your height, it’s a meaty shortboard that can handle slop and backwash like it’s not there.
if you’re not an HP board person, go with the blackbird. If you can get both, get a ghost at your height and blackbird a few inches above it. YMMV, and only one session on the ghost in pretty dreamy SD conditions.