A loop is a loop to me. Smaller is probably less noticeable. Not that it really makes a difference. If the bait is moving it is all about action to me.
More rods increase your chances but its doesn't matter if you can't handle them. To me, 4 to 6 per person is enough unless you've really got a good setup. You can set your rod tips to be close to the water, if you get something on, your tips will usually drag and you'll know it.
Just my penny.