You don't need a full cage, but I wouldn't accept anything less than picrel for a home gym
I'm not a powerlard so I am never lifting enough to actually get close to snap city or major failure, but I'd rather stay safe even if the safeties never see real use
You don't buy a gun expecting to use it, but if you ever need to, you will regret not having one
And of course the built-in pull up bar for rings