I agree with Maury82. If you are buying a different truck then the bigger is better, I guess. Like all things there are trade offs. More power, more money and typically less mileage. Will this be a daily driver for you? If so, the eco-boost makes a lot of sense.
I tow my Airstream that has an empty weight of 5380 and a max weight of 7300. I have weighed the trailer while on the road headed out for a week long trip and seldom am over 6500. I tow with a 5.7L Tundra that gets 381hp and 401 pounds of torque. I also average just at 11 mpg towing. I live in the PNW and pull over decent sized mountains all the time. No trouble whatsoever with this length and this weight. My half ton does just fine.
If, I were a full timer I probably would step up since I would be carrying lots more "stuff" with me and I wouldn't be driving my TV to work every day.
So, back to the OP, I agree that your 4.7 is a little too small for your trailer. Get something more powerful but don't think you HAVE to get a 3/4 ton or a diesel for that matter.
On the Airstream forum whenever anyone asks about hitches it takes but a few minutes before someone says you have to get a Hensley Arrow or a ProPride hitch. Check the price on those!
These forums are great but you ask for opinions. Be ready to read through them and do your own research.
