These two cars are very different, so it depends on your preference. The Citroen Basalt X is a natural upgrade from your Polo, offering fantastic ride and handling, a strong 1.2 turbo-petrol engine, and a pleasure to drive. However, compared to the Tata Sierra, the Basalt feels a couple of segments down. 

It is nowhere near as well-equipped, and in fact, the Sierra’s most significant selling point is all the tech on offer, which includes three digital screens for the infotainment system, a top-notch audio system, ADAS features and a lot more. Also, the Sierra is more spacious and solidly built.  Being an SUV, the Sierra is not as agile as the Basalt, but it's still a pleasure to drive and hence overall fits your needs better.
 

Your daily driving of 15km a day does not justify opting for the Tata Sierra diesel, which isn’t as smooth or refined as the turbo petrol. 

The Sierra 1.5 petrol is much nicer to drive, and though it won’t be as fuel efficient as the diesel, your minimal running won’t burn a hole in your pocket. The extra fuel cost will be compensated for by the Rs. 50,000 saving too. 

All new cars are engineered to run on E20 fuel, so you won’t have a problem with the additional content either. So between the Sierra Petrol and diesel, it's the petrol we would opt for.
 

First things first, you should know that some of the punch that you like about your Hyundai Creta's diesel engines is missing on modern day diesel engines. Engine calibration to meet the latest BS6 emission norms has, sadly, taken away that mid-range kick older turbo-diesels were known for. However, there are still some great diesel-automatic options available today. 

Among compact SUVs, the new Hyundai Venue, Kia Sonet and Mahindra XUV 3XO are worth a look. In the mid-sized SUV space, the new Tata Sierra, new Kia Seltos and Hyundai Creta make for good, if unexciting, long-distance diesel SUVs. 

If your budget allows, you should consider the upcoming Mahindra XUV 7XO in diesel-automatic form. The engine-gearbox will be carried over from the current XUV 700. 

The 2.2-litre diesel engine is a smooth and strong unit and is really well complemented by the 6-speed automatic transmission. It is our pick of the diesel-automatic options. 

 

Without knowing further requirements, it is hard to recommend the ideal pick for you. However, we feel the New Kia Seltos will be the best pick in your budget. 

Prices will only be announced on January 2, but assuming a reasonable increase over current model prices, you should be able to get a decently equipped model within Rs 17 lakh. The Seltos has the edge over the other two with a far superior naturally-aspirated petrol engine. The Seltos also scores for space. 

The Maruti Suzuki Victoris is a sensible package and is good value. However, the dull engine and relatively small cabin mark it down. Tata's Sierra is the roomiest of the three options, but versions within your budget miss many features that you'd expect. 

The bigger issue is that the Sierra's 1.5-litre naturally-aspirated petrol engine feels underpowered, and performance is disappointing.   

The best option for you, aside from your loyalty to the Tata car, is the new Tata Sierra. It is a comfortable five-seater with the most spacious back seat in the segment. 

The Sierra’s cabin feels very premium, too, and is made of quality materials. The driver’s seat is quite spacious, and despite your weight, you should be able to find a comfortable driving position. Go for the automatic 1.5 turbo-petrol variant, which is a bit pricey, but is a nice and significant step up from the Tata Nexon.
 

The most fun-to-drive SUVs in your budget are the 1.5-litre Volkswagen Taigun and Skoda Kushaq twins, which are very engaging thanks to their brilliant dynamics and a powerful, punchy engine. 

Both are due for a facelift, and the upgraded Kushaq is just around the corner and scheduled to launch on January 20th 2026. The Volkswagen Taigun facelift will come a month later. Both these SUVs will see some significant enhancements to the air conditioning and interiors. 

Top-end variants will come with rear massage seats, a first in the segment. However, one weakness is the rear seat space, which is relatively narrow and best for four. 

Therefore, if this is a deal-breaker for you, you could consider the Tata Sierra. It is fantastically spacious, has superb ride and handling and an all-new 1.5 petrol engine, which is smooth, punchy and fairly efficient too. 

The Sierra is not as engaging to drive as the Kushaq and Taigun, as it is heavier and has a relaxed power delivery. We would rule out the MG Hector in your case as it is too big, it's not a very engaging car to drive, and as you said, it guzzles fuel.