Hi and welcome.
The .30 luger is a sweet and easy shooting cartridge, nothing like the .30 Mauser.
Like comparing a .38 special and a .357 magnum!
By all means put one on your list; you are correct about ammo being more expensive and somewhat more difficult to find. But the shooting experience is worth it, after all- the .30 luger or 7,65mm is where the Luger journey started.
I do doubt you will be able to stop at the four you have mentioned.
