I think you're being selective and missing some. Taveras and Scott were brought in late. Pence and Towles certainly were products of Astros development. But, Patton and Wandy aren't the only pitchers of note. Gutierrez, Paulino, Sampson, Albers have all contributed and are still inexperienced. And other than Sampson they all appear to have higher ceilings than any position player prospect in the minors except maybe Costanzo who isn't a product of Astros development.
Well true, but I guess my point is, the Astros system has been pretty barren of well thought of position players more so than well thought of pitching potential. This has not been a just last year thing either, but what I was trying to point out is that Taveras turned out to be an everyday player (yes mostly developed in someone else's system), and so has Pence, and I think it can strongly be argued that Scott has the ability to play everyday, but on this team is getting squeezed out. Wandy is the only one to really stick. Albers has made several attempts, but can't seem to put it all together and the team is having a hard time figuring out what he is, starter/bullpen guy. Part of that is because of the issues on the team, part if his performance. Sampson looks like a swing guy, which while necessary, is not exactly a real hard thing to find. The others have had too little experience to know for sure.
I am not saying they don't have the potential, I am just comparing those that have "made it" and those that have not. And while you can say some of these guys have "made it" from a pitching stance, I look at making it as being a regular starter/closer/prime set-up guy for pitchers and a regular (or close to it) starting position player. So while the guys you have mentioned have made some impressions and still might make more, I have just seemed to notice more from the batting guys breaking in than the pitchers.
And yes I am being a bit more focused on the last couple of years, but then it has been really obvious the last couple of years that the Astros system has gone in the toilet and most of the time people talk about the lack of positional prospects (justifiably). I was just wanting to point out that for all the supposed lack of position players compared to pitching prospects the team seems to have produced more bats than pitchers.
Only mentioning those that saw extend action for the first time and fit my "made it" description
2005: Taveras, Qualls (pitch 33 IN in 04), Wandy (struggle in 05 and 06, but made major strides in 07)
2006: Scott (really made impact down the stretch)
2007: Pence (nobody saw him being THAT good),
So in the last 3 years we have seen 2 pitchers and 3 hitters come up and "make it" based on my criterion. This is not to say the pitching has not produced anything, just that I personally would have expected more simply because there was more "talent" in the pitching side of the system each of those years, and supposedly next to nothing in the hitting and yet there were more batters coming out than pitchers.
I didn't include Sampson, because until they put him in the starters role and leave him there, or he rises to be more than a middle innings guy, I don't think his value is really that much. And Backe was not included because he came from TB where he was already breaking in, at least with Taveras and Scott their first real ML action was with the Astros.
And right now on this team, it seems like they really could use some good pitching more than additional hitting (not that more hitting wouldn't be worth getting). So I am really hoping that one of these guys on the cusp, like Albers, Patton or the others really steps up and makes the kind of impact that this team needs. So far even with Wandy it has been more lack of better options than him claiming a spot unquestionably, at least until this year.
I guess that is more the point I was trying to make.