Will scientists improve on Darwin? Probably they already have.
Previously it was viwed as some sort of attraction between bits of matter, kind of like the electromagnetic or weak forces might generate but with a different range.
The MATHEMATICAL PRECISION for reporting on the measurement of gravity's action certainly improved, but Newton's theory was not, in and of itself, improved one whit. It's still there. You can learn it in a day. No big thing. Einstein's theory is completely different.
We recently went through something similar when the humane genome was decoded/coded. Instead of having one gene for each protein we ended up having a million proteins and 30,000 genes.
Obviously something was going on that had not been anticipated by the then current theory of evolution.
The motive force for this finding is still a mystery although there are some tenative approaches under development ~ they all have to do with theories of information flow, least cost energy pathways and quantum effects at the macroscale. The earlier theory was more about eating lunch and having sex than anything else.
I'd suggest the basis of the theory of evolution has now changed so much that no current text is really up to date.