That's what that button (circle with 2x) means on both of my Chevy fobs, so I hope that's the case here. The one with the truck and 2x is probably frunk, which would be a nice feature.
I'm not going to hold my breath, but It looks like SK ON is starting domestic LFP production later this year. If Slate keeps that partnership then the next generation of Slates could have them as an option. Would love a retrofit for first gens.
In terms of the low speed sound (including backing slowly) that's a federal requirement, although a distinct sound for backing would be nice. For startup do you mean having the truck chime at you when it's turned on?