The deck mounted tracks are used for most sailing conditions and point of sail. Since the sheet is led outside the cap shrouds, you are limited in the angle you can sheet in. You're good to a close reach or about 40° off the wind. For pointing higher, you can lead the jibsheet inside the shroud and reverse diagonal to the cabin top track and use the cabin top winch to winch in the sail to close hauled. In practice, this is a lot of fiddling for 10° higher pointing. Sailing that close to the wind is slower too, if you look at the polar diagrams. So generally, it's not worth the effort.
I find those cabin top tracks are really good at grabbing toes as you try to move forward from the cockpit.
@jssailem gives sound advice on the headsail. The B&R fractional rig on our boats are design to get the driving power from the mainsail. A small 110 jib provides less proportion of the driving. The jib does develop the slot effect of the combined sails which adds speed. I would not recommend a 135 for this rig. An additional benefit of the 110 is the ease in tacking without having to coax a large headsail across all of the rigging and reset.
If you want more sail area, talk to your sailmaker about a mainsail with positive roach. Positive roach adds sail area to the leach of the sail. You'll also want to add battens to help maintain the shape of that additional sail area.
The additional sail area will help only in light air. Even with the standard sail dimensions, I find our boats are getting overpowered at 15knts sustained and start reefing the mainsail. Second reef and headsail are furled at 20knts sustained.
