Good economy with unsafe car

Good economy and average, low maintenance cost of car, value for money but lack of power and safety. This is my second dezire but I lack power on highways, lack road gripping on speed around 100 also the cabin is noisy at this and speed above it . The fibres inside the car like the dash board, doors and back tray start vibrating and noisy after few thousands km run. The body is so soft that even normal wear n tear causes dents on body its unable to resist little to normal accidents.