I enjoyed the mathematical challenge of quickly calculating sums and differences. It feels quite good to get perfect balances, and the customers are suitably impressed when it happens.
The price of fake weights was always larger than my current money, even when I saved money from previous rounds, and even after I bought cinnamon and earned 6600 in tips for 7700 profit in a single round. (I played until day 9 or 10 with way more money than rent before I chose to stop)
Thieves randomly robbed me early on, so maybe that caused me to be unable to afford some early purchases that snowballed into me earning less money each round.
Not sure if tipping is about speed or accuracy, but I always wanted to be more accurate.
It also would have been nice if it was more obvious which scale had the more valuable spice on it, so that I could know which one to prioritize. I often threw a small weight on every scale so that I could hover to see the buy/sell price.