What financial documentation should I provide for my soft power visa application in Thailand?

Soft Power Application (Hanoi):

I'm planning on applying with Muay Thai and would like to give my application the best chance of getting approved.

I have the seasoned 500k in an unused personal account, and while I know income isn't technically a requirement for soft power, I'd like to provide something since I hear thing are getting more strict.

For the past 2-3 years I've been receiving a monthly allowance (3k usd) from my parents (bless them) and can show regular monthly deposits into an active account (different from the 500k account).

My questions are...

Would providing bank statements of the account my parents send the 3k from each month be helpful?

Would it also be good to include a letter from my parents stating where the 3k each month comes (pension and investments), so the embassy can have confidence of me not working in the country?

Or is all that overkill and it's better to just provide my bank statements and explain my situation in the cover letter?

Appreciations!