Sat Dec 21, 2019 11:09 am by MHM
Mate, the possibilities are almost endless. You're at a very exciting stage with your picking, because you've only barely scratched the surface of conventional pin tumbler locks, let alone move on to other locking systems like dimples / levers / discs / combos / whatever.
If you choose to carry on with standard pin tumbler style locks, there is a whole world of fine tolerances, high security locks you've probably never even heard of... even something as simple as a narrow, paracentric, European style keyway will add a level of complexity that you haven't dreamed of.
The Reddit belt ranking list gets given a hard time by certain sections of the picking community. But it's a bloody useful tool for someone at your stage. I'm on my phone and it's a pain to link, but just google Reddit lockpicking belt ranking list and you'll see a reasonably good if somewhat American centric list of locks graded roughly by difficulty. Figure out where your skills currently rank, and choose something from that level or the one above.
Cost...I hate to break it to you but once you get serious about hobby picking, the locks get waaaaay more expensive than the tools. Guys tend to hold onto high security locks, and once you start stripping and beating really tough stuff, you're probably going to need to buy the locks new (or get really lucky second hand on eBay).
Have a look at the Reddit list...where do you think you fall?
Best wishes,
MHM.