60W is proportionally larger than 45W due the volume vs surface area problem. So larger chargers make most sense if not for travel, for home use, so its corded bigger home and folding pins smaller travel. That's just physics.
Then the subtlety is what you do with the lower wattage "budget", say 45W.
- dumb: a 30W and a 15W port.
- intelligent: 45W to both ports.
As negotiations cannot be in parallel, they must be in sequence, so numbered ports.
I also think verified working together chargers and batteries, so a say a 15Ah Powercore is tested to work with say a 45W Powerport.