Ok, the slime will receive the same treatment ahahah
For the tilesheet, I'm planning to do as follow:
I can use one of these two tools to get the basic for the terrain:
https://wareya.github.io/webtyler/
https://www.tilesetter.org/
and then I can edit them following the instruction of the document that you have linked and this video:
In the following days I should be able to recover completely from this stressful period and get back to Aseprite!
If you have other suggestions or request feel always free to ask, it's a pleasure to work on feedback received from you game creators :D