Jagrover , I straight away suggest your uncle to TD Ford Ecosport , and then ask him if he is really hooked on Sedan.
ES really fullfills all the criteria mentioned by you except the one (sedan) mentioned in the title of thread.
Second choice would be Verna or Linea Both stands nicely on economy criteria.
I am against scala for the poor GC. However if he is used to low GC cars then you could consider this also.
Manza\SX 4 is better highway sedan than city due to their size and turbo lag as compared to verna , linea.However if backseat comfort is of importance then only he should go for these car .
AFA Vento , Rapid , sunny are good cars but do poor on economy and ASS
front.Spare cost is too much. ,
ES spare cost is at par with Maruti /tata due to localisation boon., and ford has better brand value than them.