Although technology continues to rapidly improve, and there is still huge amounts of room for interesting research, have we started to reach diminishing returns in terms of pure fundamental science?

The way I see it, from 1500 to 1960 we went from not really understanding basic mechanics or biology to having a understanding that goes right down to the fundamental mechanisms of atoms and DNA. Even in 1900 we didn't know if we were the only galaxy, we didn't know what powered stars, we didn't know why gold was yellow, and we didn't know the mechanism for inheriting biological traits. These are fairly basic large-level things that we simply didn't have answers for, and these answers came from developing new fundamental theories in physics etc.

But now we've reached a point where there isn't much that can't be explained in our current fundamental theories. There is plenty of research to do, but it either involves solving complex applications of our fundamental theories (e.g. we can easily solve for a hydrogen atom, but we still need a lot of work to figure out the behaviour of a weather system), or by making small tweaks to the fundamental theories, with the knowledge that they should still give basically the same answer in the end. As an example of the latter, if we find something "deeper" than quantum mechanics, then it must still give the same answers as quantum mechanics right down to a very high-energy or very small (below subatomic) scale. It won't be revolutionary like Newtoninan mechanics or General Relativity or Quantum Mechanics whose predictions are necessary for quite basic questions (like "Why is gold yellow?"). Even things like dark matter and dark energy still have plenty of room for explanations without hugely changing our fundamental physics.

I see it as being like mapping the world. You start out with a crude map of your local area, and over the centuries you explore and develop better tools until you have a pretty good map of the entire world. You can continue to improve this map, and sometimes there are quite significant improvements (getting rid of "phantom islands" etc), but it's a bit silly to think that we'll discover a new continent just because we went through a stage of rapidly discovering new lands (America, Australia etc).

So... what do you think? Is there no more room for big revolutions in science, and therefore we have completed the scientific revolution? Or are we still in the "middle" and there are big holes that can't be patched up without flipping things all over again?