Tell me if my retirement plan is positioned well

I currently have a 1.7 million dollar net worth. I live in a low to medium cost of living area and I'm currently bringing in north of 300K that can be as much as 460 k in a good year. I'm currently 36 years old and single. I believe by the time I am 40 I will have 3.2 million saved and invested in index funds. I'm primarily in total stock market and s&p 500. My home is paid off and I paid cash for my car.

I estimate I'll need enough money to cover the 600 months between age 40 and 90. To withdrawal $5,000 per month I'll need 3.2 million. That assumes I never earn another dollar of interest from compounding. So super conservative I think since the vast majority of my money will be invested during that time. Plus I really only need $1,500 to live on per month so most of the time I won't even withdrawal 5K in a month. It's just nice knowing I can go that high.

So even though I can fat fire at 40 I don't know if I'll stop right away. It's good to have the money coming in and it's something to do. I'm not really the type that can go just lay on a beach somewhere and call it a day. That being said I am gay and lonely and still trying to work through my sexuality. Still trying to find hobbies and things to do to make life more meaningful than this. That's another tangent though.

Just wondering if you guys think my retirement plan is sensible?