Computer Modern, the typeface built for TeX using Metafont that gives academic and research papers that signature, serious look, was designed by Donald Knuth with the guidance and advice from Hermann Zapf.
Using Times in a document implies to the reader that the author/typesetter either doesn’t care very much about typography or is being pushed around by some overbearing external style guide or clueless client. In the latter case, it is possible to use Times well and produce workable documents, but it takes a lot of extra hard work on the part of the typesetter.
If your only goal is to fit more text in, there are dozens of better choices.
Reviewers will actually criticize authors for using CM, preferring to have the extra information.
Anyway, forget about ACM. What's as space-efficient as Times and also prettier?
There are also some TeX-friendly math glyphs http://ctan.sharelatex.com/tex-archive/fonts/mnsymbol/MnSymb...
Fonts are so divisive!
The main problem I have with Times isn’t that it’s overused, but more that it’s inappropriate for many contexts, and the specific implementations of Times are often bad. If you want to use Times at 8 pt, 10 pt, 12 pt, and 16 pt in the same document, and you pick up a typical digital implementation, at least some of those sizes are going to look crappy because there are no specific fonts included for display or caption sizes. If you need small caps or lowercase numbers you’re out of luck. If you want good kerning you’re going to have to manually adjust the kerning tables. (Not to mention, Times just doesn’t look very nice or even in the best case.) By contrast, Minion is an excellently designed and carefully implemented typeface which has been one of Adobe’s gems for decades and seen lots of polishing.
I think Butterick’s comments are inapplicable in general in this example: we’re talking about an academic typesetting his own documents not a professional typographer doing a paid job. But even in proper context, I think Butterick is being a little silly here. The job of a typographer is to figure out the client’s needs and solve the client’s design problems. Sometimes that means turning out stylish layouts that turn heads, but just as often that means getting all the little details right so the design gets out of the way and lets the content shine for itself.
Don't let the name fool you, the font is optimised for readability which means you can drop the font size and it will still be easier to read than CM at a higher font size but you get more space to work with.
\usepackage{charter}