Oh wow, I was inactive when the re-write ping went out, but this is exciting news to return to!
Testing out the re-written generator, it looks great. Very easy to use once you get used to the adjusted layout, makes garden creating much easier.
I remember for really detailed gardens I used to copy and paste out the different layers between overlays on a document to organize them and test them seperately before combining them and then editing them further, this definitely makes that process much less complicated!
A few possible issues I've found, plus some test gardens for visual reference:
Garden widths shown are 250, 425, and 350. All gardens have two of the same seed listed.
Sprites sometimes get cut off on smaller gardens. I haven't noticed this happening on wider gardens, but 425 and under I ran into this a lot. This garden has 2 trees, sometimes with smaller widths there would only be one visible as the second was placed outside of the garden width.
Sand(Palette) doesn't seem to be able to re-roll the ground colour; when re-rolling, the grass ground type is placed over sand even if no layers have the grass ground type selected. It's difficult to see in this image but the garden there is set to sand(Palette).
Currently there is nothing showing up to set a custom sky gradient. Setting the sky as custom right now gives a transparent background.