Free operations and warzones and space combat (f2p need to unlock weekly).
More XP (though cartel market offers XP boosts, nearly not as effective)
Can't get over 350.000 credits, with some legacy much more expensive (although you can purchase them with coins, and don't need to unlock the globals again if you already got them of course)
Option to mail credits to other people or ask credits for you item. Also 1 instead of 8 slots.
That seems to be about it?