It’s not wrong to hope that your viva goes well but working towards being prepared is far more valuable.
You can hope your viva will be short but it’s better to read, rehearse and take steps to being ready to respond to questions.
You can hope for “good examiners” or take a little time to learn about who you’ll be talking to.
You can hope for a great viva. That’s not a bad thing to do but it’s far better for you to do the work, prepare and aim to make your viva as great as it can be.