.223 is good caliber they shoot really good and could kill a larger pig but you might find your self with not enough gun goats are not a problem for the .223
Go with .243 there’s no pig or goat it won’t stop some underrate there the power of that little pill but I’ve took down some huge boars in western nsw and north qld and more goats than I can remember.
.270 is a personal favourite of mine there a hard hitter with plenty of thump at longer rangers on larger game but can get a little more expensive to load if your shopping hole in paper for fun.
Having owned.223 and currently owning both .243 and .270 can’t go past the .243 it’s a great all rounder for Australian conditions.