the answer is easy: the LA that sucks most to mine. Try Atrax Park, when you can handle the Atrax OA/Prowlers/Stalkers
In case you know a bad-ass mob-LA has good precious stones, go mine there. 99% of the miners refuse to go there cause they find big mob (or any mob) disturbing for their dropping flow in carpet-bombing.
So go clear an area of nasty mob and mine there, results will be the same like pvp-mining but without pker-confrontation.
i gave the best answer so far
-Miners Mountian: overmined but still nice collection of stones for
ALLkinds of mining days, even if that means copper for one of those very dry days(i didnt say way too overmined yet)
-Longbulli-LA: not too bad but lowcost stones only, which can be dangerous when you amp big. And terrudite is no stone to rely on only.
...but i think you make a mistake with that question: good spot doesnt necessarily mean good LA and if, its coincidence only