The problem with using outboard
leads is that you are forced to sail the boat on a jib
reach. Which means a very powered up headsail, and powered up main. In effect you are always 10 degrees low of where you should be. So your tacking angles go from 90 degrees to 110 degrees just from jib trim. By pulling the leads inboard with a non-overlapping jib your tacking angles tighten from, oh say 90 up to 80 degrees, so you can either pinch to blead speed or foot for power.
Load on the jib track is pretty easy to control. I actually think the best backing plate for jib track is another piece of jib track installed on the back side (same size and already pre-drilled). But a piece of G-10 works fine as well. Even in a storm the loads on the track aren't that high. Even on a big boat the lifting load is far less than 1000lbs.