I hate cement boat ramps. 

Sarah,

I can't describe what needs to be done any better than you did.

Laszlo

   That is the quickest and simplest way I can come up with Laszlo.

I figured I cant be the first one to have to do this.

You have it under controll but here's this...

I use Dynel fabric for rub strips, usually a couple of layers. Here’s a lift from Jamestown Distributors page…

"Dynel fabric has very high abrasion resistance but swells in the resin such that it works better if vacuum bagged or pressure molded. The most common uses of dynel are for wear patches on boats, edgings on paddles, and the like. It has also been used as a deck covering on wooden sailboats. It seems to be a good choice anywhere that abrasion is a major issue. This Dynel Fabric retains a milky appearance when saturated rather than turning clear in the resin like fiberglass."

Because it remains milky I add graphite to the mix to make it black, looks more intentional that way. Tape off the area just outside of the patch to keep your varnish clean. When filling the weave drape the fresh patch with plastic cling wrap and tape it taut. That’ll give it a nice smooth finish with very little or zero sanding. You can massage the curing epoxy through the plastic to shape it. Added benefit of graphite is it doesn’t require varnish, the black protects it from UV.

Cheers,
e

   Sure ............sand, epoxy, and revarnish. I do it once a quarter to several places on the hull.  Concrete ramps, rocky beaches, oysters, stumps, pipes, docks, all reach out and do a little damage.

   review these ideas.    http://forum.woodenboat.com/showthread.php?174678-Keel-Protection

VHMW  1/2  or less will take a little deflection.  Like the strap idea on down in posts.