heres the best advice i can give a new coach - outside of getting a mentor, which you are apparently all over (and that is great).
1) dont expect to win right away. a lot of coaches pick up a team, screw them up royally for 2-3 seasons, jump ship, and start over - MUCH more successful. its just the way it goes, takes a little getting used to. on the other hand, some coaches get right into it. but the point is, dont read too much into your level of success in the beginning - even though its d3, a lot of the more successful d3 coaches have played a long time, and you cant expect to beat them. your goal should be to just get a handle on the game, and start to hand it to the simmies, and try to get more and more competitive with human coaches
2) read the forums. there are some total BS ranting threads (ive contributed to theses particularly much lately, with the political season, and me being an idealist who drowns the reality of how ****** politics is these days in a bourbon bottle. got to love that old kentucky bourbon!). you might want to just skip over those threads, but normally, there are a LOT of valuable threads from new coaches and older coaches alike, asking questions, discussing various topics, and such. you can read back a few weeks and get a huge jump start on the game. id also strongly recommend reading the coaches guide, its a little out dated but it was written by one of the best coaches in HD history, so its a great starting point. also, id check out the thread from aejones called "winning in d2/d3" or "how to win in d2/d3", someone bumped it within the last week. and finally, if you go under interviews, WIS asked me to do an interview i dont know, six months ago? i am long winded and tend to try to answer questions in great depth, so i answered all their questions and told them to pick their favorites, but they published it all. so its really long, but there is also a lot of good information there, too.
so yeah... thats about it. i highly recommend, on the what team to pickup thing, trying to find a conference with a bunch of human coaches, and preferably one that is active (if the last 3 posts are from admin, telling you abuot openings in other worlds, its not an active conference!). taking part in the community and getting to know your conference mates is one of the most engaging and rewarding parts of the game. at least, it is for me, and a lot of other coaches. for some others, not so much, but to each his own!
good luck!