Thailand is safe, my family has been vacationing there for 15 years. everything is cheap, i think we usually spend around $1,000-2,000 a trip on excursions food etc ( no including hotels)
We stay in Phuket at the JW for a week, the john gray tour is always fun especially with someone who has not been to Thailand before. Bangkok is a must for first timers. I highly recommend bike tours in Bangkok its a easy and safe way to see parts of the city you never would otherwise.
Obviously going to see the elephants and tigers is fun, we have a friend we have made over time that owns a elephant Sanctuary. Very private one on one with the mahouts.

Anyways highly recommend it.

dm me if you have any questions