I don't think that there are any "modern" series for which I would do this. I feel that if I can't remember what happened in the earlier books then I am probably not that interested in reading a new book in the in the series.
For example, having hacked my way doggedly through the existing "A Song of Ice and Fire" books, I'm not interested enough to bother with the "Winds of Winter" when (if ever) it appears.
I am more likely to reread when the series is "old" and it's taken me some time to acquire a book.
It works exactly the opposite way for me. The "old" books that I read in my youth and middle years are firmly in my head, the whole series usually quite clear to me so a reread is usually not necessary.
Many things I have read in the past few years though, like "Bruno", or the Novik dragon series, are absolutely not there at all and I have to reread to make sense of what is happening in the latest book.
PS I am loving Songs of Fire and Ice which I am reading hand in hand with watching Game of Thrones for the first time. I am being careful to follow behind with the books. It is the perfect escapist world to move into now that the real world has become so unacceptable to me.
Off to watch Episode 3 of Series 6 right now....