Can I ask my contractor to redo a tile job I'm not happy with?
We can't really answer the cost or any legal questions (OT per our FAQ), but it's unanimous that this job was done poorly. Repairing it right will likely involve removing everything and starting over from scratch. There's not enough benefit in saving a few rows of tile and it would make the thin set and grout work more difficult. Ripping up the floor in the bathroom is more difficult the better your contractor did their job. A power chisel will make the job go faster, but no matter how you do it, it will be a mess.

I'd point out the mistakes, ask him to correct it, and if he refuses, never work with that contractor again. A good contractor is willing to fix their mistakes and make the customer happy, since a good reference is usually worth more than the materials and labor.