Well I can understand your desire for neatness but...
If you get a new logbook and copy everything into it neatly the CAA are going to doubt the veracity of the entries (otherwise known as "Parker" hours, after the pen). Also presumably your instructor has been signing the lesson entries - you'd have to persuade him/her to sign again.
Messy is good - it will be a much better memento of your flying as time goes on.
You don't have to restrict yourself to using just the space on one line - if you want to enter a lot of useful stuff after a particular flight just use the next line. There's no reason you shouldn't do this.
H