Let me suggest you add a basting/melting cover, a cast iron griddle press, a good set of spatulas and some sort of hard cover for the griddle.
I have a 12" round basting cover and it works well for most stuff, but I've needed a larger one on occasion (like trying to do 2 Philly cheese steaks at the same time) and have been eyeing a large Blackstone basting cover at my Walmart. It's nice, but the $49 price tag has kept me away. Also, I keep thinking I can make my own by adding a wood handle to a much cheaper roasting pan.
A round 8" cast iron bacon press from Amazon works OK for smashburgers and bacon, but in hindsight maybe a rectangular one would be more versatile.
I bought the Blackstone spatula set at my Lowe's. They are heavy duty and work well (don't forget to flatten the back to a 6000grit mirror finish, with a 60° primary and 25° secondary bevel ,
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