Bigger the blade, the more lift it will give the bait hence the more weight needed to keep it down; the inverse of this is also true, the smaller blades push less water and will move much faster and provide less lift to the bait hence you can use a smaller weight bait with these smaller blades. I have some 1 oz spinnerbaits that I throw on ledges with a solo size 7 willow leaf blade- an absolute killer during the summer months and I have some smaller 3/8 and 1/4 oz spinnerbaits that I pair up with small blades, generally size 4 and down.
I'm not sure if that exactly answers your question or not. If not, feel free to send me a message or reply here and I will do my best to help you further.