Today I abandoned batch painting marines and had a go at painting up a test marine. In terms of colours I followed the Tale of Painters recipe pretty closely but I moved the order around a bit. Here's how it went:
Green and based.
Base coats. Then black lining and black wash on metals. I should have washed the chest eagle at this point but forgot.
Done! Highlights (in all cases I touched up the original colour and edge highlighted). All that's left to do is put a squad number on his shoulder and varnish him up...
Overall I'm pretty pleased with how he's turned out. It's not the fastest method of painting marines and the edge highlighting look is pretty stylised so won't appeal to everyone but I think they'll look nice on the tabletop as it gives them a bit of 'pop' that might not be there if I'd gone for a more realistic blended style.