Have done a few dives near Vancouver. Really liked the invertebrates like all the stars and big anemones. Do you have that on your shore dives? Which ones are better if you do. Seals sounds cool also. Went to your Boston Scuba web site. What sort of depths are your charters or does it vary? Did not see a list of sites.
We tend to stick around the Boston Harbor Islands. Most of our dive sites are about ~45 minute boat ride from the marina. We tend to cater to open water divers in the summer and a lot of the dives we do are shallow (less than 60ft). Most people are lobstering and scalloping and a lot of these dive sites are 30ft-60ft where people do well.
We try to hit some of the wrecks around Boston Harbor when we have enough interested people.
One of the more popular boat dives that we do is Graves Light; it is one of the outer most harbor islands in Boston Harbor. There is a decent sized seal population year round out there; Some of them are pretty inquisitive and will nibble on your fins. It's a rocky ledge that goes down to 60ft-70ft in some areas. You can find northern red anemones, frilled anemones. It is great for lobstering and you occasionally get large schools of fish. It is a nice dive when the conditions and visibility are good.
Dive Sites | Boston SCUBA
A few other good sites are 3 1/2 Fathoms Ledge (another rocky ledge that drops down to 80'), Martin's Ledge, Nahant (East Point, Egg Rock). Wrecks like the Romance (80') and Herbert (100'), Kiowa (50') are also very pretty when visibility is good.
Cape Ann (45 minutes or so from Boston) also has some really good dive sites. I'd say they have slightly more variety and a chance for a little bit better visibility than some of the sites we dive in Boston Harbor. A lot of the sites in Cape Ann frequented by Cape Ann Charters and Cape Ann Divers are great for sea stars and anemones (Saturday Night Ledge, Halfway Rock, Burnham Rock. Same thing with a lot of the deeper wrecks).
There are some shore diving sites that are great for invertebrates too but in my opinion you tend to have better luck on boat diving.
For the variety of invertebrates like Vancouver, Eastport, ME is the way to go. Some of the best and most unique diving in New England but it's a LONG ride and out in the middle of no where.
If you're looking to do more wrecks or deeper dive sites in the technical range, Cape Ann Charters (Daybreaker) and North Atlantic Dive Expeditions (Gauntlet) run great operations.