Depot charging vs. en-route: what's your fleet strategy?

We're spec'ing our first electric box trucks for urban delivery, and the biggest fight is charging strategy. Our depot has room for a few slow chargers, but the math gets ugly if we want to run two shifts. Are any operators here using en-route charging for medium-duty, or is that only viable for long-haul semis? Also, how much real-world range hit are you seeing with full payload in stop-and-go traffic? I'm worried about the difference between the brochure number and what we'll actually get back to the yard with. Would rather buy more trucks than overbuild the depot, but the utility upgrade costs are scary. Curious what's working for others.