Apologies for the long post... for those looking for the punch line, scroll down!

Seeking advice, but first some background.

I used to road race in high school and college, and then I had kids. (The horror.) A decade later my lifestyle has settled enough to get back on the bike. I am slowly getting back into shape (have dropped 35 pounds off my peak, with about 15 to go...) and have gathered enough fitness since March (starting literally at zero) so that I'm now a solid C+/B- club ride rider. (My point here is that I think my progress is pretty good, not that B- is the goal!)

I started my reintroduction to cycling by purchasing a 2010 leftover Trek Fuel EX 8 mountain bike (to replace a really out of date rigid), which has been a good way for me to get some strength back and mix it up between road rides.

For my road bike, I am still using my old racer: it's a CAAD3 aluminum frame with 53/48 cranks, ultegre rear derailed, and just a six speed cassette. I did replace the straight block that was on it to provide some more forgiving gearing.) The bike is in good shape, though virtually all the components are worn (though fully functional) and really out of date.

My challenge is this. I'm now looking to expand my retraining back into group rides, since nothing will get my speed up faster than a little competition. The problem is that with the gearing I have, I am virtually always out of sync with those I'm riding with. I have no compact cranks, so I can't spin on the hills, and fewer gears in rear means I have to shift more times over a narrower range to keep in sync.

Other vitals: I have no plans to do any road racing in the next decade. I'm turning 40 this year. I live in Western Mass, which is a great place to ride, and I have lots of riding partners and groups available to me.


THE PUNCH LINE:

I have three options in mind:

1) I could upgrade the drivetrain on my current ride. I'd love to hear opinions on this. I'd need to complete drivetrain and wheels I suspect. My CAAD3 frame is a mere 2.8 pounds, so it is weight competitive with today's bikes.

2) A local shop has a 2011 Trek Cronus Pro leftover, marked down to about 2k. It's full carbon, full ultegra. When I saw this bike (which, incidentally, I'm not sure the shop salesperson realizes is a CX bike) I suddenly started to think it might be a great choice. Here's why: I live less than two miles from the start of the D2R2 ride, which takes place each August. I can think of no better way to set a "goal" to my season than to have to conquer that bear each year, and it seems that the Cronus may be just the bike for this sort of ride. I'm also told that the cronus rides fast and light with slicks on it (very much like a great road bike, I'm told), yet can also be fitted with knobbies and fenders for some winter and offroad fun.

3) I could just keep riding the current rig.

Oddly enough, my wife is supportive of my sport, so that makes her relatively indifferent to the bike purchase decision and expense. I don't have gigantic budgetary concerns, but 2k is certainly quite a bit to spend on a "I think this could be good" bet....

Without having the wife or budget to direct me, I'm hoping some of you guys would weigh in?

Thanks!

--Thiel