I have owned a boat of some sort for over 40 years. Currently we own multiple boats and have a cabin on a big lake (our third cabin over 20 years). Boats ownership is quite common here. While I do not own a pontoon....I did drive and consider buying one before buying our 23 foot Cobalt glass boat w/ 320 hp motor with counter rotating "duo" props. It WILL blow your hair back.

I also have a 16' fishing boat and jet skis. All are fun to operate.
The pontoon I looked at actually was a large "tri-toon" and had an i/o engine...and would do over 55 mph!! Very smooth and powerful....and this size pontoon (as well as smaller ones) have become quite popular on our lakes here in MN. I was quite impressed with the toon....but still am drawn to a v-hull run-about.
The size your talking would be more of a 50 to 60 hp outboard model I believe. With a 4 stroke engine they are very quiet and fuel efficient. Easy to drive and nice riding...unless its real windy or high waves....and then you wont want to be on the water anyway.
Late model or new boats are extremely reliable, and efficient. I cannot remember the last time I was broke down on the water....it just doesn't happen if you take care of your equipment.
Dont let those scare posts above blow you away from days of fun on the water. From what you describe....I believe you could own a nice new toon and motor / trailer for around 20 K ?? Do some internet searches....lots of deals to be had.