I think you are preaching to the choir about the concept of "focused" here!
As of now, my collection includes:
- Probably close to $400 face in pocket change from my roll hunting, including a complete set of nickels except for the 1939-D and a couple war nicks
- A smattering of US classics that I got for free or cheap for liquidating an estate
- A bunch of random bags of world coins that are cool, and wouldn't be worth the effort to try to resell them on
ebay- An abandoned attempt at a US Philippine type set
- An abandoned attempt at a USSR type set
- A half-baked attempt to start a type set of Queen Victoria; not even organized or inventoried
- A mostly complete Panama type set up until the 60s (also abandoned)
- A ~40% complete Tokugawa type set
- A ~90% complete modern Japanese type set (missing several $250+ coins and all of the gold)
- About 115 out of the "official" 207 Roman emperors, wives, Caesars, and family members (my current focus)
- A meandering and poorly focused Indian type set, from Gandhara in 500 BC until shortly after independence (mostly Ancients until the Muslim dynasties)
- Pushing close to 300 Gadhaiya Paisa at this point, and still counting!
- Random ancient coins I find cool, including Greek, Celtic, Persian, Central Asian, and Chinese.
Talk about a lack of focus!