I think that we a few more people with that T.H.O. attitude to prevent open-source libraries from stagnating. It is a good thing that the incumbent 'standard' library gets regularly challenged by contenders. Without continual selection and reselection, evolution dies and progress stops.
The argument that we only need just one of anything is really unhealthy. It leads to mediocrity: I present J2EE as a perfect example. One of everything you could possibly want, put it all together and what do you have? Crap.
I think you might have misunderstood me or I didn't make myself clear. My point is if you have want to do something better, then do it in the open source community. Go at it and have all the fun you want. I think the open source community needs and thrives on forward thinkers. At least there, you will have feedback, tons of people testing, and a chance for your idea to mature. But, I believe doing that on a corporate project is risky and prone to maintenance nightmares. Why? Because generally they have not gone under the same scrutiny an open source project has.
When I learn some new technique or have some crazy idea, I write it in my spare time. If I like it, I'll publish it on my site. Now, there's a lot of things that I did (like LazyCollections) that I would never do on a real project. Why? Well, LazyCollections was a chance for me to play around and try things out. I thought the experiment might be a helpful learning exercise to other people. But, the code is generally hard to understand for most developers.
I have empathy for the people that will have to maintain my code. Generally, this means I don't code things that I can, but what can be easily tested and maintained. It's not dumbing down the code or the design. Simple designs don't need tricks. They just need thought and lots of it. Simple designs are not easy and generally not the first solutions you come to. They are hard work.