Hi theseeker, let me say that I like the people who choose a murderbox

For your sleeving with blue accent, since I'm making a mod with sleeving too, I've been thinking of color accent a lot of time, and after looking a lot of charles build, my conclusion about that, it use a simple graphic rule (same used in photography, graphic design, cinema, etc) the rule of 1/3 2/3 proportion

Add more blue, just 1 line is not enough, try 2 black, than 2 or 3 blue, than all black