My memory for specific dishes is pretty poor, and I always hesitate recommending specific dishes because there are too many variables - different taste buds, likes/dislikes, dietary restrictions, who is cooking that day and the quality of the ingredients, whether you are ordering only for yourself vs. the family/guests. I have no hesitation in stating a general principle for ethnic restaurants if you are experienced in that type of cuisine - look for items that you don't often find in similar restaurants, and look at the house specialty section. I figure the odds of finding the exceptional items are highest if you go with that. Hope that helps.
Abbruzzi is about 3 blocks - on foot, from the station, go up Richmond or Clarence up a block to King, turn left and Abbruzzi is almost at Talbot, next street west of Richmond.
For Vietnamese, Ben Thanh is just a block south of Abbruzzi. If it's a nice day and you are staying in the core, consider walking to the Quynh Nhi (55 Wharncliffe N), the parent restaurant to the Tamarine, in a building shared with a garage (insert joke here!. The trip will take you across the Thames River, the Museum London, and Labbatt's Park, one of the loveliest old school baseball parks you can find.
For Chinese and close to the core, consider Spring (768 Dundas Street), which is still walkable. It's in a comparatively rundown area that's working hard to renew itself. The decor is not its main strength, but some of the dishes are very good. If you are planning on catching a show at the Aeolian Hall, this would be an excellent place. BTW, not sure what you would regard as "traditional" but Spring is more authentically Asian than most other Chinese restaurants. Don't confuse this with The Springs which is a newer, more upscale place west of the core.
For Italian, we just went to La Casa for a birthday party, virtually next door to Abbruzzi, on King opposite the market. Quite a few fish and seafood choices, mainly salt water rather than fresh water species. The same owners run the Black Trumpet, not far away on Richmond.
It's difficult to get reservations at The Only on King, but it is one of the more acclaimed restaurants in London (enRoute, Where to Eat in Canada, etc). You might luck out. I read that one of the co-owner/chefs is leaving which may or not affect the experience there.
For a slight twist on the Italian idea, there is a Serbian restaurant called Kantina just around the corner from Abbruzzi and Casa. They have a website if you want to check out the menu in advance.
For dimsum, Dragon Court is our usual choice, but the other one we like is the Hong Ping on Horton, just south of the downtown core. Both are "pick the dishes out of a menu" rather than cart style operations.
London's eating scene is far more varied and improved compared to 30+ years ago when I first set foot there. Your foodie daughter may have some experiences of her own to relate. Enjoy your visit.