In order to make it even better in the future, improved integration with other vendors' solutions could be beneficial.
FortiGate is compatible enough with other infrastructures, but I encountered difficulties when attempting integration with other infrastructures. So, better compatibility could be an area for improvement.
Another area of improvement could be in terms of changing passwords. For instance, when using FortiGate firewall, you can have the option to set up SSL VPN, allowing users to connect to the network externally. It's like using FortiClient software. But here's the thing, when you have a local account on FortiGate, and you use it to access the network, there is no option to change your password, and that becomes a problem. Especially when you are not using Active Directory and instead relying on the local FortiGate database to create accounts.
The admin creates the account for you with credentials and a password. But when you try to access using the VPN client software, you have the ability to change your password, and that's not ideal. It's quite challenging. So, if you need to change your password, you have to contact the administrator to change it on the equipment, and that's not convenient, especially in large environments. So, that could be the only solution.