I think most of the good info has been provided but I'll throw out a few...

If you make it to Steveston, try Steveston Pizza. They've got some interesting toppings. However, I don't think they sell by the slice anymore. Probably my favorite pizza in town.

If you make it to Granville Island, just off of it, west along the seawall, there's a "shack/trailer" called Go Fish! in False Creek Harbour area. Yes, the do fish and chips but they also do excellent grilled fish tacos and sandwiches. It's not exactly just another greasy spoon as it's the side creation of the owners of a set of fairly successful tapas restaurants.

Just to add on Fish Cafe... I haven't been to it in about a year but it's definitely one of my preferred value fish places. Could be an option on route between UBC and Richmond if you visit the museum of anthropology.
I probably wouldn't recommend the Cannery because it's probably be too confusing for you to get to.

Mountain Equipment Co-op on Broadway might be an interesting place for you to visit. Maybe check out their website www.mec.ca first.