In terms of collecting focuses, I guess mine are probably fairly common.
1. I'm just setting off on the journey to build a high-grade competitive registry set for The Joker (1975), called "Eat Your Hearts Out!". Even though this run has only a fist-full of books in it, I expect that it will take some time (and even more luck) to complete in high grade. The census numbers for 9.8's across the set are both dauntingly, and excitingly, low.
2. For fun, I am collecting The Joker vol 2 (2021) run raw (I also have the 1975 run raw and enjoy flicking through these in my spare time).
I also like collecting classic Joker, Scarecrow and Batman covers, Batman-related homage / cover swipes and whenever I see those hounds (Batman #395, Dynamic Classics #, Batman #227 (and most Tec 31 swipes), I have to have them! I mostly pick these books up raw.. but when there is a deadset classic in the mix, like Batman #227 or Batman #251 - then I have to go graded!
Which leads me to...
3. My primary focus - 1st appearances of Batman villains. But, given I am average Joe, this will usually mean I'm looking for things like 1st Silver Age or 1st Modern appearances over the Golden Age. Honestly, I'll probably make my own rules a little here and there and bend some others... for example, the likelihood of me owning Batman #1 for the 1st app of the Joker is somewhere in the vicinity of zero. But, maybe I'll be able to pick up a (very low grade) Detective Comics #168 and fill that slot with his origin and I might keep that seat warm with a Joker #1 in the meantime... etc etc... 😬
To be frank, it's taken me a really long time to really settle in on this theme as a primary focus. I got lost in the weeds chasing any Bronze Age 1st app for awhile and, while this was fun and also allowed me to flip some great books to help my family when I needed to, it feels good to hone in on a primary focus and make sure I spend my meagre comics budget in the right way.
Growing up I loved lots of books but my top three were Batman, The Phantom and Wolverine. Obviously Wolvie is a deadset weapon, but the thing I loved about The Phantom and Batman was that they were just men. Men who had motive, means, morals and a vigilante streak. I could relate more to a normal man than I could a mutant or an alien... even if I didn't have the "means" part of the equation. Over time I was more attracted to Batman's tech and the awesome villains he had to face down and the Phantom fell by the wayside to become a fond memory, while I just followed Batman. So, while I've read a bunch of Marvel, Image, Dark Horse, Golden Key etc.. I feel like I've always been a DC guy at heart.
I was a little surprised that I couldn't find a competitive set for a Batman villains theme (although that could just be PEBKAC) so I created a custom set, called "The Rogues Gallery". It needs a LOT of work/love/sweat/tears/dollars to make it what I envision it to be... both in terms of the hunt but also in how it will eventually be presented. But, I'm excited about it and this journal is a way to capture some of my thoughts and experiences as I go.