A professional cover looks inevitable. Every element seems to be the only reasonable choice, which is usually the result of eliminating far more options than were kept.
It works at thumbnail size
Most readers meet your cover at around ninety pixels wide. If the title is unreadable at that size, the design has failed regardless of how it looks at full resolution.
It respects genre without copying it
Genre conventions are reader shortcuts. Signal the category clearly, then differentiate within it.
Typography does the heavy lifting
Amateur covers usually have adequate imagery and untrained type. Spacing, weight, hierarchy and restraint are where professional work becomes visible.

