Spouse Visa Holder Moving to US While Keeping Japanese Job

I'm on a 5-year spouse visa (not permanent residency) and planning to move to the US while keeping my job in Japan. I intend to:

1. Submit a 5-year re-entry permit before leaving.
2. Become a US tax resident but continue paying into the Japanese shakai hoken (社会保険) system, which includes both health insurance (健康保険, kenko hoken) and pension (厚生年金, kosei nenkin).
3. Inform my bank, ward office, pension office, and health insurance provider about my temporary leave.
4. Use my in-laws' address as my registered address in Japan.

Questions:
1. Are there any legal issues with using my in-laws' address for official registration?
2. How might this move affect my visa renewal or long-term residency plans?
3. Are there any US-Japan tax treaty considerations I should be aware of?
4. What other important steps or notifications am I missing?
5. Are there any specific considerations or limitations I should be aware of, given that I'm on a spouse visa rather than having permanent residency?

Any advice from those who've navigated a similar situation would be greatly appreciated. Thank you!