Not sure what degree bit I use, don't think it really matters since you are not doing any actual cutting of material with a drag bit.
Don't overthink it, pretty simple.
You have the choice of using the quick engrave feature in which case you can select a drag bit for tool then proceed to either do an outline [profile] or a fill [pocket] Crosshatch is an option too, takes more time but sometimes gives a better look.
Experimentation is in order to get best results.
When you use profile or pockets drag bit will not be selectable so chose an engraving bit or vbit for tool. I pretty much go with defaults, once you have created the file and have everything set to go, engrave is the easy part.
don't forget to mirror and flip the vectors, else when you turn it around it will be backwards.
Not always necessary, for instance any text you have to flip, if it is a star or something that looks the same either way, then you don't.
Here is an older thread with lots of experimentation of different cutting strategies in plexi, probably would not have turned up in search since it is not edge lit viewtopic.php?f=27&t=23152