So far i'm enjoying the game a lot thanks to a decent combat this time around.
But the amount of filler content and the lack of dialogue choice is really abysmal.
Don't see why one would complain about filler, since side quests actually adds substance to the over-arching narrative; be it in the form of fillings gaps regarding the political turmoil--exploring the ramifications and the continuing conflict of the war in various ways--or expanding the world through monster slaying or simple side activities like treasure hunting or card games.
Sure, if you want to simplify it you can argue that side quests primarily revolve around the same concept: talking, investigating, killing and more talking. But that is a huge disservice, since the beauty lies in the detail and what each quest offers differently from the other. Naturally there is a range in quality, but the majority are far more engaging than what I've come across with your regular RPG.
As for dialogue, well that is subjective. Geralt is a pre-established character, so it is limited if one compares to games like BioWare. I personally prefer this method, since the dialogue flows more naturally and adds avenues for Geralt to come across as a living individual in the game, without coming across as binary.