I am, finally, getting to the point of purchasing the epoxy and fiberglass for my first Guillemot build. I read just about everything I can and would like to get some practical guidance on which system to use.

You have waded into the middle of the "two boatbuilders, three opinions" zone... ;-)

You will find 'fans' of most of the major brands, I think. (You might add Raka to your list, as I've seen it favorably mentioned for both epoxy and fiberglass.)

I use WEST epoxy and I've never had much trouble with the pumps.
Other brands (SystemThree which blushed badly for me, ColdCure, EAST- a terrible ripoff product) I've used over the years have always convinced me to go back to the WEST products.

About fiberglass- I usually get glass from The Composite Store (US online supplier) but I've learned through hard experience that you need to know exactly what you are ordering, as not all types of glass 'work'-i.e. drape and wet-out easily- for boats. I'd recommend buying from a supplier that sells a lot to kayak and canoe wood-epoxy builders. If you are putting together a 'glass order, think ahead as you may find that some heavier glass (and carbon fiber?) may be useful if you are making glass parts like seat, coaming, hatch recesses, deck fitting recesses, etc.