If 3 adults are going to sit on rear seats then leg space is a bit compromised for long routes. if they are kids, no problem.
I bought swift because I needed a hatchback, been using it for a couple of months and I would say It's a great car. If you buy a clean car and keep it maintained, it won't give any issues.
So far I don't have any complaints, easily do 120, 130 on highways.
Comfort is quite reasonable, I have done really long travels in one go.
Boot space is ample. 60/40 split for back seats.
just doors rattle a bit on really rough roads and I am thinking of doing door treatments.
Original oil filter and air filters are a bit overpriced 1800 and 2800 but are imported and of really good quality and justify the price. Cheaper Japanese also available.
On the other hand, If you are talking about city 06 - 08. That is a better option for comfort-wise. It's a reasonable car for a family of 5. The average of honda city is also a bit better than swift. but not a huge difference.
Clean Swift gives a reasonable mileage of 10 - 12 city, 15 - 18 highway. Plus you will get a much higher model swift in the same budget so
Bottom line: If big boot space and ample rear leg space and low maintenance is your requirement then go for city.
As this is your first car, I would recommend going the cleanest car possible with as much less abuse and less mileage as possible. This is very critical. Don't try to save 1-2 lac and buy a car with compromises. Buy a lower model but a well-kept one. Ideally first owner even if little expensive than market price (and it will be expensive than market price).
Keep 30-50k handy to spend on the car once you buy one. You will need it to change all fluids, filters, and tweak the car to your likeness (armrests, visors, etc.)