Load rating

I'm trying to calculate some rough numbers on my RF wheel load with my spring/ and bump combination, for overall travel and bump gap settings. I know these will not be 100% accurate numbers but something to work off. Is there a target wheel load number to be reached on the RF at let's say 3.5 or 4" of travel? And how about the curve/ progression of wheel load. Is it better to have a nice progressive gain or a sudden gain like I estimate a dual stage setup to have? PM me if needed, thanks for any help!