In terms of ceiling and opportunity, I think your the best bets are Felix, Liriano and Diamond.

Zumaya and Neimann have some health questions to answer, for me. Zumaya with his max-effort delievry, and Niemann with shoulder soreness this year. I like their ceilings, but they seem to have high injury risks.

McGowan and Durbin seem overrated to me. They seem to have good raw tools, but haven't been able to translate them into good success, yet. Their numbers have been ordinary, certainly not indicative of a #1-2 starter, so I wouldn't bother keeping them in my league.

From what I've read, Maine doesn't have great raw tools, and his performance in AAA has left much to be desired. So he doesn't seem worth the risk.

So, I'd keep Felix, Liraino, and Diamond for sure, then depending on your roster rules and your feeling about taking additional risks, Zumaya and Neimann could be good bets. But I'd cut the others loose.

artie - Reading through your post and your analysis, I would agree with the three you mentioned, Felix, Liriano, and Diamond.

However, if Zumaya, Niemann, or McGowan had better injury histories, I might take one of those three before Diamond.

Reading the other day about his stuff and makeup, he seems like he would be a good pitcher, but not an elite pitcher (more of a #3, rather than a #1 or #2.)  

I think Felix and Liriano both have great chances to be a #1 (more so for Felix) or #2 (Liriano - likely #2 now, possibly a #1 later); Diamond's stuff according to one scout was not great - his fastball was good, but his breaking stuff was flat and his command was not pinpoint; the scout was more impressed by his demeanor on the mound rather than his stuff.

In fact, it was hinted that Diamond might be #3 on the D-V-D (Danks, Volquez, Diamond.)  

Considering the analysis and arguments on the other pitchers, I might take Diamond third only because of his injury-free history and the opportunity he is likely to get with Texas because of their lack of pitching, but I caution that, in my opinion, he is not in the same class as Felix or Liriano (and probably not Zumaya, Niemann, or even McGowan) but has a better injury history than those three, so I would take Diamond third only for that reason.  

Durbin I'm not convinced about yet, although his pure velocity and stuff I believe is better than Diamond's; if he was a little more consistent, I would also consider him before Diamond.  Maine's stuff is not better than Diamond's so he would not get strong consideration from me in this list; I would take Diamond first over Maine.

Just my opinion. :-)

At the same time, I think Diamond is more of a #3 starter - nothing wrong with that - just about any team would take a solid #3 - Texas certainly would, as they can use all the pitching they can get (no offense, Rangers fans.)