Thanks for sharing, miss this city already.

One of the first things I did when I arrived in Bkk in 2011 (my first time in Thailand) - visited this park. Lush vegetation, monitor lizards - a tropical fairy tale.....

How I see it in the 2020s: Lumphini Park is the most famous park in Bangkok, but not the best.

Benchakitti Park - the most modern, with long skywalks over ponds full of lotuses and birds, just amazing. I consider this park to be in the top10 of Bangkok attractions.
Bang Krachao - an adventure on bicycles, available at each pier. They also have cool restaurants and cafes there like this
Suanluang Rama 9 Park - a park of botanical garden type, huge, love it.

If you want more: 3 parks at Chatuchak - Queen Sirikit Park, Chatuchak Park, State Railway Park - not just trees, a lot of beauty, details, locations. They make a huge space.