The range is fine. Did you overlook that it has an LFP battery? LFP batteries do not suffer increased degradation at either end of their charge range. You can charge to 100% daily and run them down to 0% (although if you leave them at 0% parasitic drain could drain them below the built in below-0% buffer which can be bad).
The other common EV batteries suffer increased degradation at the high and low ends and it is generally recommended to stay in the 20-80% range except on road trips. Then charging to 100% just before you start and driving down to 10% if you are going to recharge soon after back to above 20% is OK.
Let's first consider non-road trips. With level 2 home charging and a 200 mile range LFP EV like the Slate, I could actually get 200 miles between charges. I'd be cautious though and try not to let it go below 10%.
That's 180 miles of usable range.
On a non-LFP where I only get to use 60% between charges (80-20%) I'd need a 300 mile range EV. That's more than the 262 mile range of the 2027 Chevy Bolt which is doing fine and costs more than Slate. That's also better than or close to the most popular non-Tesla EVs in recent sales, namely the Chevy Equinox, Ford Mustang Mach-E, and Hyundai Ioniq 5.
For road trips it is a little different because even though LFP won't be harmed going to 100% it, like non-LFP, slows down when you are trying to charge with high power DC chargers, so it is almost always faster to just charge to 80 and get back on the road than charge to 100 to get maximum distance before the next stop. The LFP still punches above its weight on road trips, but not by as large an amount as it does for around town use.
On a road trip, past the initial segment when running on home charge, if we assume the Slate will be going from 80 to 5% and the non-LFP is doing 80-10%, the Slate would be equivalent to a non-LFP with around 215 miles of range.
For people who won't want to use it for long road trips (road trips long enough that you would have to charge before reaching your destination) it should be fine.
BTW, for long road trips charging speed is generally quite a bit more important than range as long as you have enough range to cross the gaps between charging stations. The Ioniq 5 is widely considered to be one of the best long road trip EVs because of its fast charging even though its range is smaller than many competitors. It is 800 V so can accept very high power without excessive heating, and its charging curve stays high for longer than most others. (But you need a trip that has high power chargers, which most Tesla Supercharger stations lack).