>>11055255There are robot versions of a lot of folk as you can see with
>>11055316 >>11055355 but Metal, Mecha 2, and Mecha Knuckles are the only ones with any personality or ongoing story. Mecha 2 and Mecha Knuckles only recently with scrapnik island in the comics where one wants to live in peace with the other abandoned robots and Mecha Knuckles can't cope and ends up being destroyed for it. More than likely rebuilt later, but unknown as of now.
Metal however is special for various reasons. He's often viewed as Robotniks right hand man and greatest achievement as Metal is on paper better than Sonic in every way. Metal also has personality from the comics and some small story arcs giving him character development. He's my favorite character so I would like to see him fleshed out more but IDW is cancer, so hopfuly when it dies and hands the IP to another studio they can run with him. We had a bit of a moment with pic related, but it never went anywhere.
You can do a lot with him, play with him engaging with Surge more as they are analogs of one another. If they add Sage to the comics I would love to see him engage with Robotniks new favorite. Or really any robot wishing he was real trope. You can't go wrong, dude is just the best.