Snapshot for sure since if you're spamming shots as fast as you can you'll adjust to the slightly faster rate.
Meh to rapid shot since it provides no real benefit if you're not spamming your RA macro and it's pretty easy to miss. Sure it has uses and your cat1's are limited so getting it can help, but I wouldn't put it above archery/marks merits, or even first couple str merits.
Of course what you do with your range really changes the order of what you want, but snapshot is pretty much always the winner. Rapid, not so much high on the importance latter.
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80 Pup Brd, 75 War Rdm Drg Sam Mnk Pld Bst Thf Whm Nin Smn Blm Rng, 72 Drk, 63 Cor, 50 Blu, 40 Dnc Sch