I would recommend using very short test runs using a wattmeter or ammeter to measure the maximum static current draw of your setup. If you are drawing too much (or too little) current, you'll know immediately and can make the necessary adjustments. With this information you can determine about how much thrust is being generated and your probable flight duration. You can use a timer set for your calculated flight duration for your first flights to avoid LVC. I think you are right to be concerned about overheating under static conditions, even when current draw is within a motor's specifications. The airflow is not as good as under flight conditions.