I would like to typeset math in Times New Roman and have tried installing the mtpro2 fonts, with no success. I would like to know if there is a package that offers an alternative in correcting the shortcomings of packages like newtxmath: I would especially like to change the way greek letters, sums and integrals look like – apart from other details.
Here's an example of what I get with newtxmath (varvw option selected):
Here's what the same formula looks like in a Springer textbook (which has the looks I'm aiming for):
Notice the completely different integral / sum signs, the different slant of the letter χ (the letters δ, ε, and λ, among others, have the same issue), and the way newtxmath "compresses" the letters in the limits of integration.

mt2pro: https://www.ctan.org/pkg/mtp2lite. You can use alsomathastextpackage. Can you add your minimal example? – Sebastiano Sep 02 '20 at 09:06mtp2liteis not present in the MacTeX distribution; as I said, I've tried to download it but haven't managed to make it work so far. – giobrach Sep 02 '20 at 09:09tlmgr conf auxtrees add path/to/the/texmfto attach the tree and then you will have to either add the map in the document with\pdfmapfileor use updmap-sys to activate it. – Ulrike Fischer Sep 02 '20 at 09:56sudo) and re-run the installer script linked above. "There appears to have been an error in installation." – giobrach Sep 02 '20 at 09:58