So let me just ask - how much effort does someone have to put in to a level 1 gil spamming robot named aklje dsssdfds?
Would that same person go through the trouble of leveling up to a level 5 gil spamming robot named aklje dsssdfds?
I propose this - there is almost no reason for a level 1 character to ever send me a tell. If there is a reason for a level 1 character to send me a tell, then it is probably a friend and I would be expecting it. So how about on the friends tab, you allow your players to set a threshold. A simple check box with a drop down or fill in the blank option at the top of the friends list tab. Check the box to block tells from characters under level XX. New friend just started playing? Uncheck the box so you can tell back and forth until they get setup in your LS or FC or friend list, then check the box to go back to ignoring level 1 aklje dsssdfds.
Thats my 1000 characters. Really stingy on the character limits, I had a longer post, but oh well.