Considering that the Depp/DS film will be shot in England, chances aren't very good that any house that's located in the US will be used for the exteriors of Collinwood. And as much as I love Seaview (and I LOVE it!), and as much as I love its use as Collinwood in the daytime series, with its architectural style leaning more toward French than English, it's really all wrong. It made more sense for Collinwood's original backstory in the show's first year (that Jeremiah built Collinwood for Josette). But once that backstory was tossed out during the 1795/76 storyline, the style of house that Seaview is was very weird indeed for an English family to have built.
Actually, a year ago I was researching what types of houses in England might make for a good Collinwood if they decide to use an actual house. I never had a chance to get back to that. But by posting this topic, you've given me the incentive, so I should get my act together and get back to it sooner rather than later...