Professional publishers do not print using Microsoft’s “Times Roman” font. Instead commercial fonts are used. I don’t know much about these, but I’ve been looking around the web.
A font called “Bembo” seems widely used. Unfortunately the character map does not include polytonic Greek. I don’t expect these fonts to include Syriac, but that much is a minimum.
I’ve also been looking at the text itself. It needs to be kerned, which it seems can be done in Microsoft Word. It also needs hyphenation, because justified text usually gets areas of whitespace in the middle of the line unless you do this.
What else? Well, lots, probably. I just wish I could find a useful guide to this, rather than working it all out by trial and error.