Most of what I cut is in the range of a Quarter inch and some as thick as 1/2". I am not so thrilled with 1/8 wood except in special cases, 1/8" basswood can be bent into a 360-degree cylinder, but as I use a lot of depth engraving, the 1/8 of most are quite tricky to get good depth without going through
Not every wood is good at 1/2" as char makes diminishing returns where there is more of it. but Paduk . Maple, and Walnut do very well at that thickness. in any case cutting one of these in the thickest of any species you have will give you a good reference set. That can give you the ball park numbers for what you would like to work with.