There are some great options for an interesting excursion.
These options are not included in the 3 nights/ 4 days programme
Perhaps you have your own idea, please discuss with Manida.

OPTIONS

Option 1: All day trip 
Excurison to Ubolrat dam and lake, visit Big Buddha statue and temple, 
swim in the lake, eat in the restaurant Ban Saen 2.
With car/driver/guide: including gasoline and lunch: 3,500 Baht

Option 2: beauty treatments or additional massages.
Price about 300 Baht per hour.

Option 3: Half day trip
Excursion to Kosamphi forest reserve, lunch at lakeside restauarnt
and visit swimming pool (when open).
With car/driver/guide, including gasoline, lunch and pool entrance: 2,500 Baht

Option 4: All day trip
A day trip to "Pattaya 2", a beach on the other side of the lake where you can swim and eat sitting under umbrellas right at the beach. Great all day trip! (About 1.5 hour drive one way).
With car/driver,/guide including gasoline, lunch and lunch: 3,500 Baht 
 

Option 5: All day trip to King Cobra Village and/or Dino museum
Visit the King Cobra village (about 120 km go and come back) and/or the dino museum (160 -180  km go and come back). 
With car/driver,/guide including gasoline, lunch and lunch: 3,500 Baht 

Option 6: Half day trip to Silk village
A trip to Channabot (silk village). This is mentioned in many guidebooks, however in Channabot is only a big shop where you can buy silk and non slik products with a museum of the different silks of Thailand. Much more interesting is a village 15 m along the road where silkworms are kept and the actual weaving goes on. One needs a little luck that the villagers are around to show you their craft. If you don't buy anything, give them a little money as a thank you for showing you the process. We saw silkworms, cocoons, the making and dying of the thread and the actual process of dyeing the silk. A lot of work!
With car/driver,/guide including gasoline, lunch and lunch: 3,500 Baht 

Option 7: Day trip to Khn Kaen Zooand waterpark
A very nice trip is to the Khon Kaen Zoo. The Zoo is spacious, green and unexpectedly interesting. A great bonus is the free entrance to the waterpark on top of a hill overlooking the scenery: green and quiet. This trip can be combined with Wat Samlaan, the Buddhist park. If combined it will take all day: from 10.00 am to 6 or 7 pm. 
With car/driver,/guide including gasoline, lunch and lunch: 3,500 Baht