GraphenePen if security is very important to you, you might want to think reconsider using a third party closed source launcher. Every new piece of software is an increased attack surface.
I recommend you take some time to make a threat model as only you can assess what's important for you and what you want to protect from whom. Security is different for all of us, but if you consider yourself "paranoid" and then install nova launcher for the better looks, something seems off to me.
Maybe a good middle ground for your threat model could be to install a lightweight open source launcher that improves your workflow and simplifies the UI. I personally use OlauncherCF which doesn't use icons at all, just plain white text on black background, it's soothing. Might solve your needs as well.