I don’t necessarily mind when some things are left out but to not use prominent characters in the first season?  I just hope it makes sense.  
I am also skeptical of them having less time to fit twice as much in. Hopefully they will get more time to do it justice. And for the love of God, don’t rush the last season like game of thrones.  They just blew it all. Normally I would suggest someone to watch the series or go back and watch it again, but I’m just so bitter with the end of it all. It just didn’t make sense. 
At least the books have all been written. I just hope they don’t decided to change too much.