Honda announced this week that they're working on fluoride ion battery tech that can boost LiOn battery capacity (per volume) by 10x. Older versions of that type of battery required heating them up to around 300-degrees, not something viable in a car. They're also non-flammable, so safer in that view. The key is developing low temperature operation and a viable electrode.
Now, take the original i3's battery, bump that up 10x in the same volume and that would be a game changer. Or, use less of that available volume for other things (what, I'm not sure) and your options would grow rapidly. Now, charging one up would almost certainly require CCS on a trip, but you could still recharge it more often so the timing wouldn't be unreasonable from your home EVSE, I suppose.
Think about some of the existing or soon to be released plug-in hybrids right now with limited range...bump that up 10x, or take away the penalty often seen by decreasing luggage capacity and again, a game changer.
2011 535i x-drive GT, 2014 i3 BEV