It's six vs. half a dozen on running individual power lines. The only thing I'd be wary of is putting a bus bar in an area that isn't *very* sealed off from the weather
. If you run individual lines, you shouldn't have a single piece of exposed metal anywhere outside of the bus bars in the battery
If you run one big line to the helm
, you'll need to have a bus in a potentially not-so-well-sealed-up environment
If the place where the bus bar is won't ever see a drop of water
or a droplet of sea spray, go for it.
The only other thing is that you can get wire sprawl if you do too much of it. Make a few decisions like that and you'll have buses and breakers all over the boat rather than confined to a single area.
It's not the end of the world though.