They will become a better and more consistent team. Find a LW with a high work-rate who isn't prone to let his attitude affect the rest of his game, shore up the midfield with a top class holding and link-player, and perhaps overhaul the backline.

Of course it's hard to lose a star player and a legendary attack but a huge tilt towards attacking football to the chagrin of the other parts of the game isn't always conducive to success. Barcelona's greatest recent success came when they were most balanced in all 3 levels and they need to utilize this cash influx to re-distribute their strengths. For example, Real Madrid's CL success has been driven by Zidane shuffling and re-focusing the midfield on defensive conisistency, risk/reward awareness, and quick link-up play with their front-line; their MF is the engine and foundation and it has balanced the team.