I ran 100 amp service panel (20 breakers) to my 20 × 20 shop and with all my 220 equipment some 120 20 amp outlets and one circuit breaker for lights, my panel is 100% full. So yes if you’re planning to add, add big. Never can have enough outlets. I ran all 20 amp that way I had the capability to run anything larger than 15 amp if need anywhere.
Jeff Vandenberg aka "Woodsconsin"