I think a city on the frontier is plenty interesting to adventurers. It's a good jumping-off point for adventures in the wilderness, and in this case, those adventures can be in the mountains, the swamps, the plains or even across the lake. The emphasis on trade brings a constant influx of transients, and they bring all sorts of trouble. Murder, thievery, disease, mayhem and any sort of mystery you can cook up could happen in Mor's End. How is that not a draw for adventurers?
As to the connection with fools, I don't think that's what we had in mind. The fact that there is an etymological link in the English language is pure happenstance. The city is named for Morrus. If we change focus now and decide to make it the City of Fools, we will be going in an entirely different direction than the one we have been going. And I wonder how much of the work we have already done would then be useless?