I thought that overall Open Secrets was another great entry in the Vanguard series. I will confess that it took a bit to get going, but once it did, which was actually right around where you are, it was excellent.
Every serious series is still going to have a stinker or two. I love the Repairman Jack books. I think Conspiracy and By The Sword are not as good as the other nine books in the series. I think The Tomb is a good book, but it's probably the worst initial series book of any series I've ever read. So if, in Vanguard, Open Secrets is a stinker, well, no harm there.
However, once you get to Reyes's trial and T'Prynn to Vulcan, things get going.
And like Jack and the Dresden Files, I eagerly await the next book in this series. I
hope that they don't chuf the twist, though.
My compliments to Dayton Ward, David Mack, and the gang for a great Star Trek series set in the era of the original series, and with great connections to that series.