Usually, unless the UI is fully cluttered and more confusing than anything, it is not that important.
FortiClient however does run quite a few processes.
There is things that normal user would not use, like the VPN option in the Lite for example.
The only issue I had when I last installed on a mid end system (the standard version) was the relatively CPU spikes and I/O during full scan. In the end, opted to install Panda Cloud AV.