Which Groupset?

I reckon with your cable length on the long bike that Di2 would be a good idea, as the distance from shifter to mech will have no effect on shift time or accuracy.

I was taken by news of the leccy alfine. But I think the advantages of a hub gear on that bike are bigger than usual.

This will happen a lot....

Ride up to nursery, load two kids onto bike, realise I'm still in a hard gear, and cant pull away.

Not an issue with a IGH.

I realise I could shift before stopping. But I have to idiot proof the bike. Cuz I'm an idiot.