In my personal work, I have become a fan of a number of other freely available and excellent Unicode Greek and Hebrew fonts.
While Ezra Sil and SBL Hebrew are the two best mazoretic fonts, bar none, there are a number of fabulous GFS Greek fonts that would work perfectly with Logos 4.
In my papers, for example, I use GFS Porson. The Unicode text that I export or copy from Logos displays perfectly in all the GFS fonts I have tried. However, I cannot choose them within Logos.
Is there any possibility that, in the future, we will be able to choose arbitrary fonts in Logos for Greek and Hebrew? I cannot see any good reason to prohibit this. I understand that by hard-coding the Greek and Hebrew font choices, Logos is ensuring that only fonts which they have tested and blessed are available. But there really should be a way to override this.
In general, the font setup in Logos 4 needs a major overhaul. Not a priority today, of course. Let's just get feature complete and stable. But in the future, it would be nice if we could make the fonts in Logos more configurable and consistent.