For a cross bike you'll want cantilever or disc brakes. The ultegra caliper brakes that you already have will not provide enough clearance for cross tires. The ultegra brake levers will not pull enough cable to use v-brakes unless you also use travel agents.
Be careful on the sizing of the lemond bikes as they are measured c-c while most other bikes nowadays are measured center to top. For example, a 49cm lemond will probably fit close to a 52cm other frame.