Is it hard for Master’s student(大学院生) to get a dependent visa for husband？

My wife will begin her Master’s degree in Saitama(埼玉) this April. We plan to apply for my Dependent Visa in September. Here are some details regarding our situation:

1. We have been married for only one year.
2. She will have approximately 3,000,000 JPY in her Japanese bank account.
3. I have approximately 20,000,000 JPY in my bank account in my home country.
4. I am nine years older than her.
5. We can provide proof of a lease for an apartment large enough for two people, starting from April.
6. She does not have a scholarship and will be attending a private local art school.

Is there a high risk of our application being rejected? What steps can we take or what supporting materials should we provide to ensure a successful application?

Edit: The title might be a bit misleading. My wife will get a Student Visa first, then apply for a Dependent Visa for me.