In 8L, you have many many many options.... and thats why the confusion 
If you are hard bent on Hatchback...then i20 is the best car.. reasons? here are they.
a) The biggest boot space(295L) found in hatch back car
b) 60:40 rear seat folding - present in base model to.
c) foot well is nice and large enough (I found foot well in punto is not spacious, and one needs to get used to it to point the locations of ABC)
d) all 4 power-windows - present in base model.
e) power steering with scalable and telescopic (this is a new feature)
f) 5 ppl can seat spaciously and comfortably
g) Hyundai's got a record till now, No car they launched till date has flopped...
h) Hyundai's are continuously making progress in improviing thier after sales and service and all... they are not treated second best (after maruti) in the country.
i) Swift is good option but, 1) swift is been seen every corner 2) It is quiet old now... would you be interested in getting a new car which is old :-p 3) It is been said that Swift is going to get re-launched with their new K-series engine.. do not know about the time-frame though.
j) FIAT is well known for their poor customer-care... (You have experienced it.. Just consider, if this the treatment you received before you were to become a customer.. how would you be treated when you actually become customer ).
k) FIAT has got awesome engines... the same is fitted in Vista .. You may wish to consider that.
l) Tata has recently launched 'Manza' it is the Sadan of Vista .. ppl say it is value for money car... You can check it out.. but consider the after sales and service (note, FIAT's customer care is been taken by TATA.. and you have the experiece under your belt for FIAT..) and build quality for Tata products.
wow!.. would go from A-Z... but i would suggest first get your requirements on paper first.. and then choose a car... if still in doubt... post it here... some guru would definately help you out...which will help me to learn too.