So we have been a 1 car family for… basically as long as we’ve been married. We’ve spent the last year with our son in daycare 2.5 mi away, continuing with only one car. And we’re due with #2 in (fingers crossed) under two months, and we are not buying a second car. Our plan to stick to one car sounds a lot like your plan to move to one car: two e-bikes. We have the benefit of starting with 1 car, though, so it’s not as much of an adjustment. Currently DH drives to work and drops off son at daycare on his way, I wfh, and I pick up son from daycare in my bike 2.5 mi away (one way, more like 6mi round trip due to a detour.) Here’s how we’ve managed the one car +bike set up for a full year of daycare thus far:
Inclement weather: We don’t live in Denver so this usually means daycare is closed when there is a snow day. For regular old cold, some good winter coats. When we get our e bikes, we’ll be getting add on canopies to protect from the wind at higher speeds, and to make rain more palatable to bike in. However, we do have summer thunderstorms and I do NOT mess around with lightning. In the summer, we would routinely check the weather in the morning. If there was a chance of a storm during pickup, either DH would bike in and I’d drive for both drop off and pick up, or he would plan to have stuff he could work on from home if he needed to leave work early to do the school pickup. This was definitely the most difficult weather to work around, and from what I know of Denver, I think that’s a problem there too? But with consistent communication and planning, we were always able to make it work.
Scheduling conflicts: because we only have the one car, we’re practiced at communicating anything that would require the car, in advance. That might be an adjustment you’ll have to make, transitioning from 2 to 1, but not impossible. With the proper planning, I don’t think we’ve ever run into a day when we both NEEDED the car at the same time. But it does take slightly more planning and consideration of the other person when scheduling appointments, etc.
Now, we only have one kid, and he’s still bike-seat sized. Our plan to not need a second car is to get two e-bikes too: a Yuba spicy curry (long tail) and a Madsen bucket bike. DH can use the long tail to bike son to daycare (2.5 mi), then on to work (another 2.5). While this is currently feasible distance and fitness wise, his current bike is unsuited to a bike seat (it’s a racing bike), hence why he currently drives. And while his 5mi commute is doable for him, we’ve also talked about how an e-assist would basically remove all friction from the decision to bike. Then I’d have the Madsen to do pickup with the car seat in the back. Even though it’s only 2.5 mi, E-assist is 100% mandatory for me, as I already struggle on the hills here on my 40 lb bike. The Madsen is 125 lb without anything in it! But this way, we will be car free at least 5 days of the week.
With the distances you’re looking at, the e- part MAY not be strictly necessary but if it removes significant friction from choosing to bike, you’re more likely to stick with it and not run into the last two concerns you mentioned. Plus, a major factor of how likely you are to stick with it is how far everything else is that you regularly need. Doctors office, grocery store, kids activities, friends houses, library, etc… bikeable? For us, for example, the grocery store is only sustainably bikeable with an e assist because it’s way downhill from home. With one car, and currently only one “Walmart bike” it’s not the end of the world, but it does mean that we have to plan who will do the store run and be sure they have the car that day.
The main concern I’d have would be locking an e bike unattended at a train station all day. Tern sells ones that fold down and might be able to come on transit with you. But given how easily defeated bike locks are, I’d hesitate to leave anything you couldn’t easily replace there.