Good stuff; I especially like the train of thought on ther sentries.
I have been thinking about a base raid scenario myself too.
But since you can establish a base in a location of your choice, I figured that you should also represent the site with an appropriate building, like a library, inn or catacombs. Perhaps each with their own pros and cons.
And I also think the base additions, such as kennels, summoning rings etc, should be represented and be 'destructable'. Certainly for campaign play, where this could force players to actually think strategically as well. And of course the band's vault!
Points for being not spotted, items nicked, base additions sabotaged/destroyed etc for the attacker. Points rewarded to the defender for spotting the attackers, base additions and vaults succesfully defended etc.
I really like the idea of such a scenario. Especially when it can be included in a map-driven campaign (great fan of those
)