There really aren’t any cons, IF you do everything right. With a hacked V1, you can make a copy of your internal storage and put it on your microSD card. This is called an emuNAND.
With CFW, you can boot from the emuNAND and keep all your hacks, homebrew, pirated games, etc. on emuNAND. This way, you keep your sysNAND entirely clean. So you can go online with your sysNAND and your legitimately purchased games, and never worry about bans.
You can do just about anything you can think of with a hacked switch. You can pirate games, you can emulate games from just about any retro console. You can run Linux, you can run Android. You can overclock, you can use game cheats and mods. You can play music and videos. You can use game controllers from other consoles on it. You can play your PC games on Switch by streaming them from your PC. All sorts of possibilities.
My personal favorite is Debian. I’m the IT director at my job, and 90% of our machines, including end user workstations, are running some form of Linux.
One really nice thing is that most stuff is saved somewhere in your home directory. You can switch between all sorts of distros, and if you install the same software, browser, email client, etc. most of your stuff will automatically be there and work out of the box.