For model stuff, check out Roma General Store
https://www.facebook.com/General-Store-Roma-134444589944034/info/?tab=overview
Via Tarquinio Prisco, 40
It's not a huge shop, but it's got some great stuff. I was there back in February and took a few pictures of the figures they had on display
Be aware these aren't necessarily the kits they have for sale (though they had a nice selection of those), just figures that members of their club have painted.
For general tourist stuff, the Vatican museum is great. There's also the Capitoline Museum and the Borghese gallery. No trip would be complete without a visit to the forum and the colosseum (single ticket is good for both). The Spanish Steps are currently closed for renovation, so don't waste time visiting them. The pantheon and trevi fountain are also good stops, though this are quick sites. No need for tours, just stop by the check them out and then move on.
Food is obviously a highlight when you visit Italy. Unfortunately a city like Rome has a lot of tourist traps, so it's worth checking out restaurant reviews. Here are a few of my wife and my favorites. All are good places to eat but also not overly fancy or expensive.
Colline Emiliane: Via degli Avignonesi 22, a small street just off the Via del Tritone (not too far from the Trevi Fountain). The door can be easy to miss, but this one is definitely worth the trip. The owner is the chef and his wife makes the dessert. You should definitely save room for dessert! Reservations are recommended.
Enoteca Provincia Romana: Foro Traiano 82. This place is right next to Trajan's forum, so near the Capitalone Museum and not far from the main forum and the Colosseum. Normally restaurants this close to tourist attractions are awful, but this one is great. Everything they have is local (not just the food by the way, so don't expect to get a coca cola).
Osteria la Gensola: Piazza della Gensola 15. Just across the Tiber from the Jewish district, this place specializes in fish. A little more expensive than the first two, but not too much. Reservations for dinner are recommended.
La Ciambella: Via dell'Arco della Ciambella 20. A few blocks south of the Pantheon. This place is built over the ruins of the Terme di Agrippa which is visible through transparent floor panels. Not too crowded with good food at reasonable prices.
Enoteca Regionale Palatium: Via Frattina 94. A wine bar but also a great place for lunch.
