Second era is less epic fantasy, but is a much better written series (better written characters etc). Depends what your looking for really.
I believe the third era is due this decade, will be interesting to see how that differs from the first two eras. (Other than probably having a lot more Cosmere connections)
I read the first book over the summer, and found out (through reviews) that the second book wasn't as interesting until close to the end, so I held off on investing time into it. I still want to get around to it, though