I think a lot of owners are busy with the holidays and a little sick of teams that haven't performed. Many of our managers are into other sports this time of year as well. Probably only a few are as fanatic as I am about checking leagues daily once their teams are out of the playoffs.

I am in four leagues where Tim S. has posted his notice that he wants to trade. I've made one trade already with Tim. In the other leagues, there are some possibilities to deal with him, but I can't make myself pull the trigger on an offer this early where there is no clear match of needs.
I had one team of the four in the playoffs this year and have three others that are in various stages of rebuilding, so for the most part I'm looking to pick up a star or two in the draft and fill some holes later in the draft, then trade as the season apporaches or right after the games start.

As to parity of trades, any manager--top or bottom of the league--who tries to trade soon gets a sense of whom he can trust and whom he can't. I know I've made some real blockhead trades in my time, mostly out of impatience. Funny thing is, I've had some really bad trades approved by the commish and then had to radically restructure some better trades to get them approved.
After all, Mike (or whoever is Commish) has his favorite players and guys he undervalues, just like the rest of us. If this game were totally a science, it wouldn't be half as much fun!
Dave N