It's not even June yet, so don't get overly concerned just yet, and don't go blowing things up unecessarily....but, it's never too soon to make a few tweaks here and there.
Dukes vs Cabrera - I'd be inclined to go Dukes if he wasn't injured. His upside is significantly higher, and Cabrera should be in the sell high mode. Melky has 3 years of 400+ ab's and yet to hit 10 home runs. He already has 5 this year. And while he's in a better lineup and better hitters park, he is also being squeezed for pt by Gardner (and Nady may be back in a month or so).
Dropping Ray may be a tough thing to do, but you may want to look long and hard at that. He is coming back off injury, and Sherril isn't doing that poorly of a job in closing now. Ray's been downright erratic so far, and it may be midseason till he's back to form and even then he may not be closing full time.
I'd take a flyer on Aardsma. Aardsma k rates and ratios are really decent and he is closing now. While Morrow may win back the closers job, nothing is certain, and worst case, you are getting a good setup man who should continue to help in other cats. I'm not sold on Soriano overtaking Gonzalez anytime soon, but it's worth keeping an eye on.
I've never been a big Anthony Reyes fan, and at this point see no reason to keep him around. Generally I like to stock up on NL pitchers when I can. The guys you listed aren't very exciting, but...
Duke isn't awful. He has a sub 3 era and very good WHIP. He gets a fair amount of K's, and while pitching for the Pirates, his 5 wins are probably about 1/2 of what you will get for the remainder of the year, he is a pretty good situational starter, imo.
I have Bonderman in one league and frankly, I'm not expecting any miracles. He's still young and can pitch effectively when healthy, but that's the problem. He only pitched 70 something innings last year, and well, nothing this year. I'd expect a slightly higher ERA/WHIp than in the past as he comes into form, but he still has decent strikeout potential if he can get the velocity back.
The others you mentioned, I'd probably avoid.
g'luck