I have a bad habit of reading things, getting rid of them and then a day later realising there was some gem of wisdom that has resonated with me and that I need to re-consult. So I can’t tell you where I read this but someone mentioned writing out your plot from the perspective of minor characters as a way of solving problems and building consistency.
I tried this for one character and it was massively helpful – revealed a few plot glitches and showed me where he wasn’t quite working. Now I have taken a different view of him (equivalent to changing his star sign, if you go in for all that) and he has really become a much more complex and satisfying person. I have literally written his side of the tale in one long splurge but I plan to divide it up and split it scene-by-scene so when I go through for my re-write, I can factor it all in accordingly. I’m onto my second character now and half way through I came up with a reinvention of her background which has made everything much more convincing. It’s also a hugely enjoyable thing to do!
I don’t think any of this is going to rewrite the plot in a major way but there’s nothing like making sure every scene works for every character to ensure it’s watertight.