There are some really good deals available on used electric cars at the moment. It sounds like a secondhand Audi e-tron might fit the bill nicely - it's not a true off-roader, but it should be able to cope with hills and muddy rural roads. The Jaguar I-Pace is worth a look, too. If you're determined to switch away from electric, we'd recommend a Toyota RAV4. It's a robust hybrid SUV available as a 4x4.