Let me start by noting that I never mentioned phasing out regular items from shops, but only those that have a character of being magical. I imagine that the armours and bows at Deganwy has a significant hampering effect on the endeavours of a woodworker or leather armourer trying to get buyers for their wares. Removing the exceptional heavy armour and weapons would also benefit the smithing trade, but I'd be more cautious with that for now. However, you should keep in mind that when the supply from NPC merchants is reduced, it's likely that there's going to be a lot more PC crafters as demand rises. The crafting system is also still far from done, with enchanting of items, among other things, yet to be implemented. Before all the rest is in place, we won't have any form of inter-dependent system, or even a fully balanced and functional server-wide economy.
I'm personally not very fond of automated systems that eliminates the buyer and seller having to actually meet though. The motivation behind having a server economy is, for us, much more to spawn roleplay - and that means interaction. I like how some set up IC messages on our forums announcing that they'll provide items for certain prices, or that they'll ask for crafters for certain items etc. An in game notice system might benefit these things even more.