It's certainly unusual, but golly it's a really slow early game and a then a suddenly rushed endgame. Once I uncovered the merchant I was wondering why he was even necessary. All I can tell is that it gives you the chance to build the "special recipe" with one hex fewer. Otherwise he was just another part I had to ignore in my fight to keep track of which towns I needed to placate.
I think two parts of the endgame that felt unnecessarily stressful was trying to remember which town's order came first, and trying to catch the orders as they came in. I think a simple visual timer would work well, maybe the hex turning red or some eye-catching color as the order got later and later? That could solve both problems at once.