The very first bike I ever rode was a 1977 BMW R100/7 (1000cc) touring bike. I had to adjust to the weight at low speeds, but feel like I am a better rider for it. Size of the bike for me today is not an issue, but it took years of getting comfortable with a big bike before I got to this point.
The most important thing you can do right now is don't outride your abilities.
You are riding with guys from the office and guys with sport bikes. Being "one of the guys" and being infested with the same "Big Dog Disease" that most of us are, you are going to be very tempted to get something that can keep up with a sportbike, and unless you are a riding prodigy, will likely get in over your head real quickly worrying about keeping up with the pack. Ride your own ride, not their's.
Buy what you are comfortable on, and ride when and where you are comfortable. There are many beautiful places in this country, and none of them are seen lying on your back while your pride and joy is sliding down the road.
This happened to me a few years back, and keep in mind I have been riding on and off for most of my life, and very seriously for the last 8 years. I got the sport touring bug back in 2006 and bought one of those 175HP 1200cc road rockets wrapped in plastic and slapped some saddle bags on it so I could tour (which is what I really love to do). I am a self taught rider (strike one) and I have no track or racing experience (strike two) and I went riding with a friend and his buddies who believe they are road racers (strike three). I was talked into going that day even though I didn't feel like riding as I was getting over being ill. That afternoon cost me a broken wrist, broken ribs, all my riding gear and $13K worth of damage to a very fine motorcycle because I was not equipped to ride at their level. I am a very proficient rider of large bikes, have ridden them for a long time and have 100,000+ miles of touring under my wing, and I was still helpless to the pressure of riding within and trying to lead the pack.
I rebuilt that bike and sold it after 5 more years of touring on it. When it was time for a new ride I went back to the cruiser to focus on touring. It's what I love to do, its why I got into motorcycling, and when it comes down to it that is really all it's about.