I have used LastPass for several years. I use it slightly differently than it is designed, but I believe that it makes it more secure.
I allow LastPass to generate complex passwords for each site, but the password that LastPass generates and stores is only *part* of the actual password on the site. In addition to the LastPass password, I also append a 4 character code to the end of each password. The 4 character code is the same for all sites, and it is known only to me (i.e.: it is not stored in LastPass).
For example, if the LastPass password is A@1niuvf&^76ThGb the ACTUAL password on the site is A@1niuvf&^76ThGbABCD where ABCD is my personal pin. The advantage is that if I should leave my browser open, or if my LastPass account is compromised, no one will be able to access my accounts because the password in LastPass is only part of the password.
This mostly works great and without any issue, EXCEPT when it comes to changing (or initially setting) passwords - it is quite a manual process. I let LastPass generate a complex password, copy the password, create my account on the site using the complex password + my Pin, then manually go into my vault and create or update the site using the generated password WITHOUT the Pin.
It would be great to have an option in LastPass where it knows that I am using a pin (but doesn't know the pin), and allow me to update and store passwords using this scheme, especially to allow me to updates all of my passwords every few months.
Probably not high on the list, but I do believe that it makes your tool even more secure!