First of all, for the ones who didn't see other routes of Fate, it's not a remake from the 2006's Fate/SN, it's just another route, so that explains why it's different in some ways the character takes along the anime.
Now, I'll show my opinion about it, since the first Fate/SN, The normal and logical rule is " Masters against masters and servants agains servants"; but why ? It's simple, servants are HEROES, warrios, they are trained for it, and master are humans, they need servants to win the war, and that's why humans can't beat servants. Fate/SN UBW broke this rule, because of the overpower protagonist, Shirou is a guy that defeated the most incredible servants of all times AND himself as a HERO. That sounds impossible, but it's a little uncomfortable for people who are expecting a new Kiritsugu in the world. I'm not saying that he HAS to be weak, only that he appears more as a student than a awesome warrior...
I noticed as well that it put all the characters more powerful than the other series, with an INCREDIBLE AGILITY... yes, this is a uncomfortable thing too, the servants and some masters ( like Shirou ) gained the ability to move faster than normal people, you can notice this on the fighting scenes. Although i like fast characters ( like Kiritsugu and kirei on Fate/Zero ), the exaggerated speed made me think I was watching a typical shounen anime, where it's very common. The difference is that on Fate/Zero, the fastest characters are trained to it, it's an ability, it means, AN EXPLANATION.
Fate/SN UBW had beautiful scenes, good moments and a good enjoyment in some episodes, the art and sound are awesome and very clear, but the story ( in my opinion ) lost for the Fate/SN from 2006. In general, it is a good anime and it was worth to watch. I didn't expect it to be brilliant as Fate/Zero, but it let me down a bit.
