Watch Towers

[Scilly_guy]

I prefer the op's idea, I agree that it might not be 100%right for the setting, but there were towns in colonial America's with fortifications, but in a pvp mmo EVERY property is defended.
With regards to just feeding "dumb" characters without skills, there could be a prerequisite skill for manning it, not necessarily a super high level skill, but one that takes a while to obtain. You could also make the towers stats a combination of humours and proficiencies, range being f&w and black bike, damage being c&d and yellow for example.

[trungdle]

In addition, I suggest the tower need skills to be used, so to put yourself on the tower while offline, you need the skill, say, "taking shift", or whatever.
And that guys on the tower can ring a bell or yell "intruder!" whenever he see someone near the town (like 1000 tiles) so that he can aware you of any TbC or poopclaim people put off to your town. This could require another skill. A very expensive one.

[Argentis]

I like the idea. Even though making an alt with decent biles is not that hard so I concur with the idea to link it with proficiencies.