18lb springs and 1.2 rockers will work and give you a bit more power. you won't have to worry about valve float with the 18lb springs either. the rockers will change the sound some since they add lift to the cam. my DB was noticeably louder after i installed 1.2 rockers (i've got a small cam too). it won't sound like you have a radical cam though. you can tell that mine has some work done when it idles, but it doesn't sound that much different than a stock 6.5 with a header.
you'll also need to get the Honda guide plate or modify the clone one if you get the 1.2 rockers.