No doubt a super cool and out-of-the-box idea, but I quite personally would go crazy if I had to hear water droplet sounds any longer than an hour.
Also, whether any particular sound is annoying or pleasant is complicated (we're just figuring out the parameters now) and subjective. So, we're working on letting users create, edit and share sound packs to see what smarter and more talented folks than us come up with.
i just had another idea, and you just have to try this and see if it works or what it does: the exact millisecond when an event occurs is not that important. I think you can safely shift an event 20-50ms in time, without losing important accuracy. You could use this leeway to space similar events apart slightly, so they don't give that glitchy "retrigger" sound effect as much. It'd take some code, but you could even buffer all events for say 200ms, and use that sliding window to space them out as evenly as possible. I don't know if it would improve things, because it's really not what happens in physical ambient sounds, but it seems to me like it would smoothen things up a bit more. You could give it a try.