I think you might be overestimating Div. IV a bit. My best Guard had 8 OD only. My best passer had 11 PA, with the 2nd best at 8. My best shooter had just 7 JS, 5 JR for most of the season and got trained to 8 JS during the playoffs.
I look at your team right now and maybe 1 more addition of a well-rounded 10k-15k salary player will probably be enough to keep you in Div. IV. I think the main thing in IV is keeping your GS 8-9 and playing the right tactics.
Good luck.