So how many ports relate to how much mah as the smaller items largely are just for a phone, larger items for tablet+phone and then tablet+phone+headphones. The more mah the more ports, but then the more variety of port types.
So <10000mah = 1 port. So we have a version with one lightning input and one USB output as then that matches what an iphone owner would want.
10000-15000mah = 2 ports. So he have versions with 2 ports; USB-C x2 say one port used for (input) recharging or 2 ports used for (output) charging. Here use the USB-PD profiles so if only output to one port then it gets more Watts, if using 2 ports each has less Watts. Then say a version with lightning input and one two USB Output.
Ultimately right now if you have multiple devices, you often see the cables as a source of bulk, so shoot for least quantity of cables, it is either just a day long and you need one powerbank only for 2-3 devices, or its an overnighter and need charger+powerbank and your cables used to recharge powerbank, so think reversing the purpose of the cables.
Currently we'd typically see the smallest physical item is the charger, then powerbank, then cables, there isn't much can be done about the charger or powerbank but cable bulk stands out as OTT due in part to Anker thickening their cables and variety of ports.
Ultimately, the total eradication of everything other than USB-C is required, this involves Anker offering USB-C versions of everything, such as the Soundbuds microB to become USB-C. You could then potentially just carry a total of say 2 cables. If Anker made a full USB-C family of products then you'd never need that microUSB cable.