Thank you for your praise and for your feedback. Actually intended progression is a bit different but we did not communicated it good enough, I guess :) What you meant to do is to use the Shovel for first runs. With its 20s dig time you would pull out 3x artifacts with slightly lowered gold reward due to not perfect artifact condition. And once you have enough gold - then you can upgrade your brush and focus on excavating perfcet ones.
But I do agree that there is something to think about in terms of time and progression speed