Unfortunately, at your budget of Rs 8 lakh on road, few cars will feel like a significant upgrade to your Maruti Ritz, even though it is 12 years old. This is also because you are looking for an automatic, and while you are happy with having only basic features in your car, the automatic gearbox is usually tied to mid- to high-level variants in most vehicles. However, here are some options, like the Hyundai Exter and the recently facelifted Tata Punch that should meet your needs within your budget. Both also use a tall-boy design which allows for easy ingress and egress, and the Punch has the added advantage of doors that open a full 90 degrees, helping further.
However, of the two, we would recommend the Hyundai Exter, as it is slightly wider in the rear seat, and also because it has the smoother and more efficient petrol engine with the smoother AMT gearbox of the two.