Its been a few years, but I got by with an inexpensive, metal handled hatchet for pounding stakes, a pair of side cut pliers for cutting wire, and a folding pocket knife for cutting bait, cutting markers so I could find the sets, and skinning. The knife line up you have mentioned essentially covers all those bases, so your on your way:thumbup:
Later on I added a Busse Natual Outlaw E, and used it to cut stakes for muskrat traps, cutting bait and clearing brush. I still have the hatchet and pliers in the old pack basket. An opinel or small buck diamondback would easily handle the other chores. I'd prob go with my Busse meaner if I had the chance to trap now. sd550 has good points, will be used harshly and may get lost.
Pick a knife you enjoy and trust, much like a good gun, part of the joy of the experience is using the tools that appeal to you. Good luck and have fun!