By tomorrow your budgets will be set, you'll see projected ratings for all players, and the trade offers will start rolling in. As a newbie owner, with a new team, there are a couple of "facts of life" about trades you need to understand before you dive in head first:
1) You are at a significant disadvantage versus veterans in judging talent. HBD is a complex simulation and it just takes awhile to metabolize all the ingredients that go into sizing up talent (more than a season nor 2, imo). I'm not suggesting that you not trade. But when you do trade as a rookie, you'll get better results if you go ahead and admit that you're starting at a disadvantage.
2) You've taken over a team, and your advanced scouting is 14. You're rebuilding and looking to trade for prospects. If a potential trade partner has advanced scouting of 18, the projected ratings he sees (for players under age 27) are going to be quite a bit more accurate than yours...particularly for younger prospects. Even worse, the converse (you have a trade partner with a very low advanced scouting budget, like 8) is NOT necessarily true (the projected ratings he's seeing could be from a couple of years ago, when his advanced scouting was higher, or they could be from his international, high school or college scouting).
What's a newb to do? 3 things:
1) "Borrow" some experience - go get a mentor (or a bunch of 'em). Go to the "HBD Mentors" thread in the Hardball Dynasty Forum. There's a list there of a bunch of experienced GM's who are willing to answer questions and mentor newbs. Try out a bunch, then pick maybe 2-3 to bombard with questions all season. This will help...just do it.
2) Ask a bunch of questions on the World Chat (like you've been doing) related to trades..."How does the groundball rating factor into stats?", "How come this guy has good ratings but crummy stats?", and "Does push/pull really matter?" are 3 good ones I admit I haven't figured out yet.
3) Make trades...with the above in mind. It's a game - a great one at that. So enjoy it and view your first season or 2 as a fun education.