You're going from a Giant composite to a Schwinn steel? You sure that's what you want to buy?

I wouldn't pay $500 for used steel. You can buy an aluminum frameset with Sora Group set for same price.

I'm not saying aluminum is better, but if you're looking for a similar ride for $500 as your Giant TCR2, steel definitely isn't it. Aluminum hydroformed with oversized headset, downtube, with bent seat stays, throw in carbon seatpost, and you got a bike that is much closer to your previous Giant.

I would look for a used Specialized Allez, Masi Partenza, Trek 1.2 for example and buy a carbon seatpost. Get a Pro Vibe 7S stem, with it's 10 degree angle, to get a more aggressive position on the bike, to get something more similar to TCR2. Maybe replace the fork with a straight one? Allez compact probably your best bet for $500.