The resources Chaos brings is more money to expand the team - that doesn't mean we get more good programmers applying, unfortunately. So having the money for them and finding them are two different challenges :) As for sharing ideas, algorithms, etc. that sure happens, but sharing code is not normally possible as our code base is different. So because something works in V-Ray, doesn't mean we can now just copy and paste the code over and presto - in fact, we might not even be able to solve it the same way they solve it, due to the differences in the engines, so even the "approach" rather than specific code may or may not be something that can be carried across. It all depends.
One thing to note is that small things like "Added render stamp.." are NOT taking away from the large tasks. Some things are not that critical, but they also take very little time to implement - why would we skip them just because some larger features that take significant weeks or months are not done yet?
And of course prioritizing work is a complex thing - work on motion blur, or instances, or R21 support, or.... ? We do our best based on a whole host of factors (which I wrote up at length some point before) to sort out the priority of doing things. Some people may never use motion blur, some use it every week, and so on. We'll keep right on working on all these things! And as ever, if you know some good developers, send them to our jobs page :)