First things first. Change the password.
It doesn't matter how long or complex the password is. If someone has access to it, they'll get into your account one way or another.
Change it. If you haven't since the 2012 Data Base breach especially.
Changing it more often is never a bad thing either. Better to be safe than sorry.
If you really want a long complex password to help yourself feel a little more secure, save it to a notepad file just on the off chance that you forget.
(you need an account to see links)
Use this website to make a complex one. You can copy and paste it directly to Neo, and to anywhere you want to save the password, and it will make it complex based off your specifications.
Secondly.
Make sure your Email is active, and hasn't been purged.
I'm sure everyone here uses an Email for Neo that is still active. But on the off chance that someone can find our Email, and realizes it isn't active. All they have to do is request your password and/or PIN. And they can change everything they want.
On top of this, there are methods for people to get the password to your email, or one of your emails. While this isn't incredibly likely to happen, it's strongly recommended that you change your email password to something that is different from your Neopets password.
ON TOP of this, you can ALWAYS change your current email.
All you have to do it make a new email, activate it, and you can change your current registered Email on Neopets.
Save any information you think you might forget to a notepad file somewhere.
Lastly.
You cannot have a PIN cracked that isn't on the "list" that people have.
That list consists of PIN's also from 2012 and before. So any updated PIN afterwards cannot to cracked. Only guessed. So if you have something easy to guess as your PIN (For instance, I'll check numbers in birthdays if the PIN isn't on my list), change it. And if necessary save it to a notepad file as mentioned before.