I just came back from Thailand a week ago, and it's still very affordable compared to other Asian countries.
I spent my time primarily in Bangkok and did not find the prices being much different than when I was there 6 years ago.
It depends what type of travel you would like to do but to give you some examples, 1 hour thai massage 350baht, street food/stalls ~50baht, restaurant in malls 300-500baht/pp.
Accommodation is also affordable for the value that you will be getting. I stayed at a 4 star hotel and it was around 1500baht/night.