I find that Auto Dig Vein mod really a great way to save time.
To make it not only save but safe, I've just started working on expanding it a bit.
In particular, I want to add the following features:
* If there's a piece of ore DIAGONALLY to the current position, cut one of the adjacent tiles out even if they don't contain ore (My gnomes often stop digging because of this)
* If a gnome would be breaking through a (known) wall, the tile should not be designated. (Prevents breaking into caves that are already discovered)
* For when I'm REALLY eager to work my way through decompiled Gnomoria: Automatic placement of torches.
-> If a tile is dug out and it would be dark even when including all torches currently designated to be built (+ the ones built already, of course), place a new torch here.
This would probably not result in the most efficient torch patterns, but would relieve the player from some tedium.
Any thoughts are welcome.
I've taken the liberty of basing my work on the decompiled sources of yours. I hope that's okay.