Kudos for wanting to try other types of blades. While a sheffield would certainly be one to try, you might want to see if there are members in your area (google map page on this site) that would let you try some of their gear so you don't have to horse-trade all of them to find what you like best. Also, should you try a sheffield wedge, don't assuma all wedges are like them. The harder steel gives a distinctly different feel. I'm jealous your first 2 blades were 1/4 grinds. They really helped me learn, and remain a fav.
I also concur w/ the suggestion to shop in the classifieds here. I didn't, and I regret that decision.