My choice would be:
1) floor mat : Noodle mats
2) car cover : tphcovers.in for upmost safety. Amazon/Flipkart for basic covers.
3) mud flap : Push dealer to give these free.
4)steering cover : Not required IMO
5)seat cover (seat cover is included in XZA varient) : I had Tata OEM
seat covers for few months and removed them from front seats as they made the seat contours disappear. As you are getting it free, I would say go for it. Try to check how it looks in any other car at your dealership.
I heard that recent models do not have boot lamp and spare wheel reduced to 13 inchers. Please let us know once you get a chance to PDI your car.