Metrics similar to EBITDA minus CAPEX Margin in the efficiency category include:
Quick Ratio - A ratio used to assess a company's short-term liquidity.
FCF / Net Income - This data item measures the ratio of levered free cash flow to net income to common, excluding extra items. It is a quick and helpful check on the quality of earnings.
Long-term Debt / Equity - A ratio that measures the level of the long-term debt relative to the book value of common equity.