I do mini sub-sets. For Example, I am almost finished with a nice, full-step war nickel set in at least MS66FS by PCGS. I also included the 3 major errors 1943/2, the 1945 DDR, and 1943 Doubled Eye (not doing full step for these errors as they can be tens of thousands of dollars in MS66FS) I also have a 1943 P-D-S steel cent set all in MS67 with CAC stickers (PCGS). Also included a 1943 D/D in MS65. Also an MS set of Franklin's, silver washington quarters, silver roosevelt dimes. Also a set of the key Lincolns only where each coin is at least $975 (1909 S VDB AU55, 14-D AU, 22 No D Strong Reverse VF35). Also key error coins in the $1,000 range (3 leg Buffalo, 1955 double die, 1942/1 Mercury) and other key cents in MS65 (1972 doubled die, 1983 doubled die). Also every single year and mintmark of every single silver Eisenhower proof or uncirculated including $1 commemorative with his face on it, every single silver and gold Kennedy half ever minted, and a complete set of mercury dimes (MS from 1931-1945 and vf-xf for the rest) Also a set of 2001 silver buffalos and some $50 gold buffalos. Next, I am saving up for a VF 1893 S morgan and VF 1921 set of the Walking Halves
I'm a type collector but if it's a small series then maybe. I wouldn't mind collecting all FS war nickels.