I'd say you need both. Coherence is important for the usability and maintainability of codebase as a whole, while algorithms often run key components of a syst

I'd say you need both. Coherence is important for the usability and maintainability of codebase as a whole, while algorithms often run key components of a system (eg A* pathfinding in a video game). Data structures are fundamental and if you don't know them your code is probably buggy.