I have a few HOF collections but mainly just two. I only collect football HOFers and I have a collection of 1st Topps Cards (for those that have a Topps card) and for those that don't have a Topps card, I do try to get their RC but that can be expensive. So I just do the best I can. I have another HOF collection and that is of all their other cards, regardless of when it was produced. I enjoy getting some of the new releases of old-time players like Jim Thorpe and Red Grange. I like the old pictures and reading the info on the cards. For those that have traded with me, they know that I prefer defensive players and linemen but will trade for any HOFer. Most of my cards are worth 20 cents each, but I'm fine with that.
To add another twist to my collecting is researching players and stats to anticipate who will ultimately make it into the HOF so I can start accumulating their cards. For example, for last years class I already had the Topps RCs for all the inductees and Art McNally's 1991 ProSet the day the class was announced. I was only missing Dick Vermeil. Its fun to work on that in the offseason.