You CAN use a party system for turn-based combat; note that you don't have to check all the boxes for any roguelike interpretation including the "Traditional Roguelike" interpretation at roguetemple which describes the "character-centric" aspect.
Entries must include elements of roguelikes, that is the reason why that interpretation is provided as a reference, but you don't have to comply with all of the elements described there, you can bend any interpretation in the name of innovation. (just don't bend so much that it breaks)