You’re welcome! The main differences are as follows:
2a and 2c are both reinforced flat printing guards with about 1/8 of the lower structure removed to clear a cable gland, with 2c allowing for complete removal of the guard without undoing the cable. 2d is the closest file to the origional guard and covers the full intake face. 2b is essentially just a flat plate. It prints easily and is the cheapest option, intended for use in areas where guard damage due to sticks is likely, but it also offers the least protection and probably the worst performance due to the eddies right before the water hits the prop.
The rear guard is also going to get an upgrade and some sort of alternative mounting will be included. Right now the easiest way without using my mount is to use zip ties off the main motor positioning arms, but that too adds drag. I’ll probably get those posted this weekend.