NB: this is a shameless plug for patristic books I've posted about in the past. I saw that MJ has really been going in deep with some early church fathers I've never heard about, and wanted to bring up general resources I've recommended in the past… especially if Logos is interested in building a Early Church/Patristics resource guide, per MJ's suggestion, which I strongly support.
Yes, although it's dated (now 20 years old), it's still Anthony McGuckin, who has name recognition, and a dictionary resource like this could really help support datasets and resource guides related to the early church, not to mention the Factbook, Timeline, etc.
If the last resource was dated, this one certainly is. I only mention it because it is now definitely public domain (no royalties or sale restrictions) and it is referenced in the Ancient Christian Commentary series, so Logos could make that highly-selling commentary series even more valuable with more working hyperlinks.
This would be huge. This resource contains primary texts from the early church, and not just the orthodox writers, but the dissenters and those who were condemned as heretics. These volumes provided me what I needed to write my paper in seminary on Eunomius of Cyzicus, when my Logos library came up empty.