Hi
I think that it would be cool to have a line in each hill for National Record (Like you have Local Record, Personal Record and World Record lines). And that you can chose what lines you want to have, so you don't have to have 4 lines if you only want to have the PB- and NB-lines.
Also, if you could chose were you wanted to have a line yourself, then that would be nice... (like, if you want to beat your friend in a hill, then you can write he's PB, and you'll see a line for that length in the hill).