I think you're hitting some good points. I've had a chance to use the Guppy Spoon a few times last winter and I used 3 pound mono line. I also fished in less than 20 feet of water so I guess you could say I was relatively shallow. It seemed to drop just fine. Of course not as fast as we're used to when using a "jigging spoon" but most flutter spoons are designed to fish slow and entice the fish on the fall sequence.
I would match the Guppy Spoon with 2-4 pound test line and fish it on a light to medium-light action rod (4 pound line on the ML action if you choose).
For me, it serves its purpose mostly for panfish and perch, not so much walleyes, so unless you tie into a "bonus fish" I think the drag system on most panfish setups will work just fine.
All that said though, the Guppy Spoon caught A LOT of fish last winter! I actually already have one tied on