What is the Funnest 2-place airplane?

I'm looking for a fun airplane to introduce my two young kids to
aviation. Here is what fun means to me....

- flies low and slow
- Side by Side seating
- can get into small grass fields
- good STOL performance
- Dependable
- Relatively decent number of planes available to buy
- low operating costs
- OK if it tie down outside
- Homebuilt or Certified OK
- Under $30k

I learned to fly when I was 12 in a C-152 and am now a 40 year old ATP
rated pilot with several thousand hours. I've done a ton of XC
flights in Mooneys, twins, etc. Cool but not viceral fun. Looking
back over the years, flying my friends Piper Cub into grass fields,
small airports and such was probably some of the best shear joy
moments in my flying career.

I want to get my 7-year old EXCITED about aviation and don't have many
ideas outside of a J-3 cub. I'd greatly appreciated any thoughts on
aircraft that I should consider.

Thanks for your thoughts