Was there a better officer to promote instead of Lütjens?

Was there anyone else the Kriegsmarine could have promoted?

Not an obviously better candidate: Lütjens had built and commanded the light forces, possessed First World War command experience, and stood out in a very limited officer pool.

The interwar navy had preserved too few officers with a broad mix of combat, staff, and sea-command experience. Lütjens was decorated for First World War service and had become the institutional expert on torpedo boats and destroyers. Those qualifications made him a rational choice for an expanding light force even though they did not make him an ideal capital-ship admiral. Choosing the strongest available candidate could still leave the navy with an officer underprepared for later capital-ship command.