Every 3-6 months, I always come back to my designs and look for tweaks. In this case, it was a cascade effect started by a very simple minor change:

Upon this game’s review, I decided to separate the Items deck that both customers and the shop drew from into their own separate decks.

• The deck being a shared resource was the initial reason I allowed an empty Items deck to be replenished by the discard pile. With this justification gone, I removed that rule for the Items deck for the Shop (now just called Inventory).
• Now that Inventory was a finite resource, I looked at its deck size of 28 cards and determined that 28 Items / 12 trades = 2.33 Items per trade was too low for my 3 cards every trade rule. So I removed that restriction.
• Even with that restriction removed, the average cards per trade was still too low. So, I added the rule that the customer's offered Item is added to Inventory resulting in 28 + 11 (the last customer's Item doesn't matter) = 39 Items over the course of the game = 3.25 Items per trade. This also felt more thematic.
• With the 3 cards per trade restriction gone, the Inventory size now felt a little too big (easy), but it's a step in the right direction. So, I reworked the game difficulty system to remove some Inventory Items during Setup by 3/6/9 resulting in 36/33/30 Items over the course of the game = 3.00 (easy)/2.75(normal)/2.5(hard) Items per trade.
• Also, more recently after some playtesting with the 3 cards per trade restriction gone, the 9/10/11-Item Shop felt too easy. So, I lowered it to an 8-Item Shop. The variable Shop sizes was unnecessary since the game difficulty was now tied to Inventory size.

All of these changes has been to drive functional and thematic improvements.

Now, the Merchants' Guild is the only new change that wasn't a direct result from the above design journey. It's basically just incorporating the "Favorite Items" variant into the base game. However, it was the perfect time to add it since it creates another decision point between managing your limited Inventory while maintaining your Reputation.

Lastly, the feedback and comments from playtesters has helped drive these designs as well. I have credited them as contributors in the game rules. THANK YOU!