one really nice new virtual compressor is the vari-mu modelled "mjuc" tube compressor and its free little brother the "mjuc jr." by klanghelm.
another great plugin is the tilt eq "niveau filter" by elysia - very helpful for quick balancing of the overall frequency distibution.
other than that i really like to use a lot of the stock plugins in logic x, just as i did in previous versions of logic. you can really come a long way by just using what you got, by just focusing on making the sounds in your head come to life thru the means of your available tools.
some of that third party plugins might get you there faster, because they are biased for a certain sound, but in the end they are also just tools and it is what you make of them.
peace, jo
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