Security is a process, not an application.
I have a very poorly written 'bonus article' on my site that's awaiting a rainy day when I'll publish it. It was written while I was really, really inebriated and there's no salvaging it, so I'll eventually just hit the publish button and let 'er rip.
Anyhow, as a general rule, I don't use any of those things - not even a firewall (on my desktops/laptops). Malware exists for Linux. Don't install it. I use least-permissions type of processes and take care to install only from trusted sources.
I don't bother with a firewall. I'm behind a router that has NAT enabled. I used to use a hardware firewall but I haven't bothered with that in ages. You can't do things like access my network without me noticing. I'm gonna see your car in the driveway! However, you could just access the guest network. It's isolated from my network and only allows internet access.
No, you can't SSH into my systems - at least not without a whole lot of work and a whole lot of information. So, I'm not too concerned.
I keep good backups and don't do much in the way of banking online. So, for all that work you're really not going to get anything. Just like using multiple browsers, I keep things compartmentalized.
Public facing servers are a whole other story. That's not really salient as this site is mostly about desktop use.