Lots of people are posting weird, exotic, faraway locations. Not many people are posting "logical" locations. I believe the three Superpower capital systems (Sol, Achenar, Alioth) have been mentioned and should be included. There should, perhaps more specifically, be plenty of "tourist missions" wishing to go from one superpower capital to another.
The other "elephant in the room" in regards to Tourist missions are, of course, the large number of Tourism planets in ED. I don't know if ED are planning to incorporate them into the mission generator, but they should consider it. These worlds are somewhat considered backwaters by players as things stand now, because they're dead-ends in regards to trade (unless you like filling your hold with biowaste) and logically there should be missions throughout the galaxy going to these Tourism planets, and plenty of missions at those planets from tourists using the Tourism planet as a hub seeking a return trip to other exotic locations, or from tourists wanting to book passage home again. I, for one, will be rather disappointed if they don't link tourist missions with Tourism planets in this way. I'd certainly foresee a lot of newbie "I went to a Tourism planet for tourist missions and there aren't any there" posts on the forums if they don't.
Most of these "tourism planets" don't "look cool". In fact, most of them are Water Worlds, not Earth-likes, so these "tourists" seem to be xenobiologists, or water/ice sports enthusiasts.
There are hundreds of "Tourism"-tagged systems in the galaxy, meaning it should be relatively easy to find one near you. Just set your galaxy map colour mode to "economy" and filter out everything except Tourism. A full list of Tourism planets would be difficult to compile but would include the following systems:
Beditjari
Dimoco
Clayakarma
G 203-47
HR 7451
HR 7925
Ngardinja
Obambivas
Wat Yu
There are still some Galaxy Map glitches with regard to Service and Tourism planets. The following systems are listed as Tourism planets on the galaxy map but have no actual Tourism destinations on the System map; I don't know if that's a bug or some as-yet-hidden "future content" (eg. surface starports on Earth-like planets) that is triggering it. These systems contain Earth-like worlds, but all are pure Agri worlds according to the system map info.
37 Xi Bootis
Audusi
Belu
BD-01 3500
LFT 1425
Palaemon
Ross 860
Shou Xing
Willapa