First Solo Travel to Thailand 4-5 weeks

I’m planning a 4 -5 weeks trip to Thailand. Already have my first 5 nights booked at a hostel in Bangkok to experience the Songkran fest, and I'll be checking out on April 16th

After that, I’m hoping to hit both the North and the South before crossing over to Cambodia. I want a good mix of partying, diving/beaches, and chilling, but I’m trying to avoid complete travel burnout and wrong plan

Here is my very amatuer solo travel plan. Would love to hear your thoughts, especially on the transit. I can make any changes after Bangkok

• ⁠Bangkok (5 nights) Checking out April 16th.

• ⁠Bangkok ➔ Chiang Mai (Flight or Night Train) should I book now?

• ⁠Chiang Mai (4 nights)

• ⁠Chiang Mai ➔ Pai (Minivan)

• ⁠Pai (3 nights)

• ⁠Pai ➔ Chiang Mai ➔ Krabi (Minivan + Flight) or any other ways?

• ⁠Krabi / Ao Nang (3 nights)

• ⁠Krabi ➔ Phi Phi (Ferry)

• ⁠Phi Phi (3 nights)

• ⁠Phi Phi ➔ Khao Sok (Ferry + Minivan)

• ⁠Khao Sok (2 nights)

• ⁠Khao Sok ➔ Surat Thani ➔ Koh Tao (Joint Ticket Minivan + Ferry)

• ⁠Koh Tao (6 nights)

• ⁠Koh Tao ➔ Bangkok (Ferry + Night Bus/Train)

• ⁠Bangkok (1 night) - Just a quick rest stop.

• ⁠Bangkok ➔ Cambodia / Siem Reap (Morning Bus)