It's very possible to do (for most values), but to develop a graphical interface for each value wanting to mod would be very, very time consuming. Each value mod has to be custom written.
I realized the work involved after writing SH3 Inspector, which only does a small part in game mods. My solution was to write SH3 File Analyzer. With it you can write a rule defining the layout for any SH3 game file and modify *almost* anything in such file if you can pinpoint the value using the rule. Rules are not easy to write, but I have written a document which describes the basics if you want to give it a go. I've written many rules already which cover most of the files you listed. It's a bit techy of a program, but it saved me 100s of hours of coding, which is what it would have taken to write more programs like SH3 Inspector.
http://www.delraydepot.com/tt/sh3sdk.htm
Hope this helps.
TT