If the top tube had not been repainted, I would have said - just take enough care of it so that it won't rust. However, since it has been defaced already, the answer is a resounding "it depends".

If you are comfortable with undertaking the task of refinishing it yourself, then it is certainly worth it. If it were mine, and I had to spend more than $150.00 to finish the task, I wouldn't bother - your threshold, and others' thresholds for this obviously might be different. That's just mine. If you want decals... mswantak can almost certainly hook you up.