We should be excited any time we have a brand new monster introduced. I am very happy when we get a break from Daleks, Cybermen and Angels (oh my). Add to that a perplexing oxymoron of a cute smiling happy robot that is apparently scary and I am ready to go.
Now to the reality. "Smile" was more disappointing to me than "Pilot". I can excuse the first episode since it was basically an (unnecessary) origin story. Origin stories are always full of prose and relatively slow. I was hoping smile would pick up with the twists and excitement.
I was sorely disappointed again. First thing they did was dispose of the comic genius of Matt Lucas, making 3 part banter impossible. Next we see the tiny bots ala Big Hero Six and the white emoji bot that strongly resembles the robot from Hitchhiker's Guide.
Our heroes show up to a mystery. Just like last week, the Doctor hypothesized a reason but was wrong. On a whim, instead of trying to fix things, he decides to just blow it up. This was probably thrown in as humor but for those of us that have been around, it's not very Doctorly. The companion discovers something the Doctor missed. He must find a way to barter peace. The solution now is to just reboot the system (where was this a few minutes ago when he was going to blow it up). And suddenly the robots are sentient beings that need to be lived with instead of blown up. 
So far this season feels a lot like we are literally going back to the beginning, when Dr.Who was an educational kids show. Today we learned that Vikings lived in their long boats, bones contain calcium and calcium is used as fertilizer. This is not the thought provoking science fiction I have been living since the 9th Doctor grabbed Rose's hand all those many years ago. I can only hope that this is still building a base on which the rest of the season will improve upon.
For now I fear I must rate this 1 Tardis out of 5.