when i was searching for a liana two years back, my uncle who is a professional car dealer said not to buy an imported liana as some parts are different from the pkdm which are very hard to find. so i kept seeing the pak suzuki versions. my suggestion will be to go for a 1.3 M13 version which is stock in paki liana. atleast you will find everything here in open market. liana is already a very very technical and not-recommended car so why going for something more complex, bigger and never introduced in paki (i mean 1.5).
ultimately its your own call. we living in karachi, unlike lahore and islamabad guys, usually never think of motorways, highways as usually we just keep our cars inside the city. and 1.3 seems very fine.