If your vessel is 27' on deck as you know, the inflatable is too big for on deck. I can only speak for myself but if I were to do passages on a 27' vessel I'd bite the bullet and get an offshore liferaft. That way, you can stow the inflatable below. You could half deflate it and stow it on the foredeck as you mentioned. Even half deflated on deck is better than below where it's useless when you need it.

In any case, as many others have said, towing can lead to real problems when the weather changes. If you're towing and the weather gets bad you'll probably make the decision to bring it aboard which can be a real challenge with a good potential of having major problems including the loss of the dink, your boat and human lives. First you need to stop the boat, point to weather, jump in the inflatable, somehow haul it aboard, deflate and then stow it, perhaps at 3 AM with 6 foot seas & 15 knots of wind. Not a situation I'd like to be in.

Of course, you could always get a larger vessel if you plan on cruising offshore. In Dashew's 'Surviving the Storm' and observations from the Queens Birthday storm, given that both vessels are of the same quality and outfitted similarly the larger vessel is more likely to survive bad weather.