Haha...

my boat still looks like the brochure!!, except add 35 years of wear & tear (& no spinnaker winches!)
I agree with the others that a mid-cockpit sheeting location would be terrible..some boats can get away with it right behind the companionway, but #1, the C-30 lacks a bridge deck, & #2, this configuration ONLY works well when the sail is up, the rest of the time the mainsheet & associated hardware is in the way. I have sailed many miles on a Tartan with this setup..great for the sailor & helmsman, but absolutely terrible for everything else.
BTW - if you do move the mainsheet location aft, you can lose some of the purchase..Mine is only 4:1, but if I had mid boom sheeting, I bet the extra loads require additional purchase..most of you guys are running 6:1 for mid-boom sheeting I assume? ?
A little bit off topic..notice the boat in the brochure picture has the short track mounted on the cabin top..My boat has this piece of track and also came with some Odyssey sails in yellow Catalina bags (I know they are original) & I've never seen a sail from Catalina fit this location..anyone else?

What is the purpose of that track?
When I start running out of more pressing 'projects', I am thinking about moving it down to the deck set up in a location for sailing close hauled with the 155% genoa to improve upwind performance since my current 'jib track' is out on the gunwhale..A simple 2 foot track with one block/car would not add too much clutter and I probably move my jib leads about twice per year but get the benefit of inboard sheeting.