Best early priority
On the first move, identify which rank is currently needed by the most foundation piles and look for that rank in the arch. If several arch copies of that rank exist, you can cascade several promotions before touching the tableau. That quick sequence often reveals your real bottlenecks early.
Common mistake
The most common mistake is spending an empty tableau column as permanent parking for an arch card you might need later. Empty columns are most valuable as temporary throughput during a multi-step cycle of a deep tableau stack.