The one big question I have is about what my goal should be this season. Should I be gunning for the playoffs, or should the first season strictly be used for training, maybe even playing guys out of position and whatnot, and should I not expect any real success for a few more seasons?
Division 5 is really easy if you want to put in some effort, and judging by the fact that you typed out long post asking for advice that seems reasonable. Manage game shape, try to build a roster of 6k-13k salary players with high secondary skills, be smart about trainees (your main goal should be to make money with them), invest in your stadium. Make sure you are making a good profit every week even if you are trying to promote. It may take a couple seasons but there's no reason you can't make a playoff run your first time. Also because fan support is linked really closely with winning, tanking isn't much (if at all) more profitable than being a decent playoff team as long as you don't overspend on salary.
Also I think you are paying too much on staff, see
(221642.1) for more info.