Since Leon couldn't use blue angel leaves, he had two options, buy potions or increase his recovery and then make better items to duplicate that effect. Both options were possible since Ilyana also stored mana potions in her vault. Besides, Leon could obtain a single coin by every slime killed, so he could obtain almost fifty thousand coins every day. However, that changed when the slimes reached level one hundred. Instead of one, the slimes gave him two coins.
"I guess that is to be expected... Still, while potions are useful, some time is lost to use them. Increasing recovery will help me more in the long run."
Although that was the case, Leon decided to first increase his health and stamina up to recovery's level. In order to make things as efficient as possible, he had to make good use of the full effects of all his status.