The single most important activity or site you would take someone, if they had never been to Doha before:
Relaxing at any of the 5-star hotels private beach and pool area.

If you ever wanted to experience the orient but do not have the funds for Dubai (or another high-end location), I strongly suggest visting Doha Qatar.

What do I miss the most when away from Doha?
Friendships & Enjoying the Sites

More specifically:
- Sitting on the beach during sunset smoking a Shi-sha pipe
- Leaping into the waters of the Gulf from the upper deck of a Dhow (an Arab sailing vessel)
- Or having the driver scare the bejesus out of you on a 4-wheel drive sand dune Inland Sea tour, ending with a barbeque and bonfire at a private camp site waterside.

Read more about Doha and sand dunes:

http://www.igougo.com/attractions-reviews-b328297-Doha-Four-Wheeling_the_Sand_Dunes.html