Yes, I definitely second this request. IFTTT already gives you one way into SmartThings, but having a direct integration with SmartThings would make it a much easier.
I'm a Zero Energy homebuilder and we're trying to include technology with our homes that is extremely easy to use, which is why we include SmartThings with every home. If it's not easy then most homeowners will never use it! It's also why we're interested in Sense. I can tell you firsthand that the average Joe isn't going to want to, or know how to, setup IFTTT as the middle-man.
Also, if you truly want to expand the usefulness of energy data and monitoring to the masses, then it should not only be able to connect directly and easily to SmartThings, but also have controls that allow Sense to automatically send commands to SmartThings "behind the scenes" so the homeowner doesn't even have to think about it to save energy. Of course, you'd want some safeguards built-in so that it doesn't start turning lights on/off without the homeowner's permission, but you get the idea.
Imagine if you could tell Sense during setup what your utility rates are so that its AI can come up with suggested alterations to the homeowner's routine and by simply tapping "Yes" to a suggested change Sense would send the command to SmartThings to make the change for them automatically. The new Alexa integration is a great first step in this direction by allowing the homeowner to query real-time energy use and then follow that up with a command to turn off lights, turn down the thermostat, etc., but at the end of the day the vast majority of homeowners won't care to even query Alexa about their energy use in the first place. Having the system monitor it for you and then prompt you with suggested energy-use behavior changes and allowing the homeowner to make the change with the simple press of a "Yes" button is what the end-game should look like! That's the home of the future I imagine being possible for the masses.
PS - I have model homes with all of this tech and would be happy to be a beta tester for a direct Sense-to-SmartThings integration. I can also help with suggesting how to connect them as I've been doing this sort of thing for a few years now.