You may be surprised how capable a two-wheel-drive car fitted with winter tyres is - but, ultimately, a 4x4 with winter tyres is the best of both worlds. Have you considered a crossover like the Kia Sportage? You can get a 4x4 version and it will be more efficient than your X-Trail. Alternatively, if you don't need much space, something smaller like the Suzuki Ignis with its Allgrip system will be surprisingly good in the snow.