There aren't many recognisable characters that come to mind when thinking about Premier Skins for Cyborg. Grid is the most obvious choice. It's an unusual Premier Skin to lock behind progress within the mobile version, however, as Grid isn't a character I'd argue the majority of players would be familiar with. It's not the first character I'd choose to promote the mobile version.
The Premier Skins that have been announced thus far have been unique characters in terms of their identity, not powers. I'm curious as to whether we'll continue to only see Premier Skins that expand the character roster, or we'll also see Premier Skins that only function as unique costumes. Is a Batman Rebirth Premier Skin, for example, possible within the scope of NRS's plans for Injustice 2? I'd much rather see a focus on expanding the core roster, albeit superficially, through Premier Skins. More Grid, Mr Freeze, Power Girl and Reverse-Flash, etc. Less Batman Rebirth, Batman (Earth 2), etc.
I'd Iove for NRS to confirm whether gender swaps are possible via Premier Skins. Choosing to adhere to the base character's gender when considering ideas for Premier Skins is rather limiting.