Cover gouged board surface with foamcore?

We are working on a board - Port of Innsmouth (hi Lovecraft fans). Some of the surface of the extruded polystyrene foam is getting gouged as we remove this annoying metal sticky paper from the foam. Also the foam has some sun damage from exposure.

OPTIONS:
1. Fill gouges. In the past (rr modeling) i filled holes with plaster, foam plugs, decopage, and other stuff. All of this stuff gets old and powdery and basically gets very hard to work with as it ages. Perhaps fill them with large and medium talus using diluted white glue . Not sure this would work to fill large gouges in the foam.
2. cover with foamcore. Not sure how i feel about this option. Would be expensive and perhaps unnecessary.
3. dig out area to make a subterranean lair/dungeon and make a fitting cover/lid to the area out of foam or foam core. Dont really have the time right now but we thought it would be fun to have the option to do it later on. Of course this would not really solve the underlying problem of what to do with the gouged out areas as the covering/door over the subterranean area would still have gouges!

What do you think the best option is?

This foam you're gouging, how workable is that in regards to doing fine cuts and controlling the surface texture? If it's an option, you could just work that foam until you've got level areas for putting minis on, and letting it stay like that.

Not sure what textures you'll want on those areas.. if you're going for cobblestone (and every table gets a couple of extra awesomeness points for cobblestone) foamcore or pink insulation foam might be the way to go. Either that, or plaster casts if you can bum some hirstarts molds somewhere.

Working with your mistakes instead of obsessively correcting them can score you a much more natural, organic final feel. That'll probably sound a bit silly if those gouges just makes the surfaces unplayable though!

I know the foam you are talking about and, honestly, in my opinion, messing with it isn't worth the pain. Option 1 doesn't work that well, option 2 would be pretty expensive for what you'd end up with and option 3 sounds painful.

Good foam board (without that silly foil!), such as Foamular250 or the blue stuff from Dow, is the way to go. It comes in 4'x8' foot sheets varing thickness (3/4" is the way to go). It'll run less than $20 a sheet--not sure about prices in California. Get the most dense stuff you can find.

Don't throw out the gouged board though... use it to make hills and other terrain pieces for either Warhammer or when you decide to leave the cozy confines of Mordheim for a Empire in Flames, Nemesis Crown or Border Town Burning campaign!