Ah. I know what you mean about Venli/Eshonai throwbacks. Those gave me a few "ugh here we go again" moments on my read through, but they do build up to give more context about the Parshendi and how/why the current conflicts starts and who they are as a people (trying to avoid spoilers as much as I can). I still think it's a bit of a slog, but I appreciate it a bit more now...

I hated book 5. I thought 4 was the worst of series until I read 5.

The ending was just really shitty and stupid to me.