as for cutting concrete vs ice, there is much more friction on the bit with concrete and so we add water most times to try to save the bit by cooling it and lubricating it. more friction means more energy spent. so we dull the bit faster and use more energy per cut with concrete. cutting ice should create water at the friction point if there is any.
cutting with basket saws in old petrified wood is super hard on drills, more so than concrete. you can't use hammer mode cutting wood. try a 6 inch basket saw in old wood compared to a 6 inch lazer in ice. you'll get far less cuts in wood and the bit will become duller much faster in wood and cause it to use even more energy and create more heat.
speaking of heat, cutting ice means working the tool in freezing temps which means less heat than using it on a hot day in summer. heat being a transfer of energy means less wasted energy in frigid temps.
depends on quality and age of battery and how many times it's been charged for how many holes you'll get and sharpness of blades and how wet the ice is and how thick and brand of auger because of attack angles, but as for a 600 inch pound to 4 inch lazer auger your fine. i used a ridgid 500 inch pound ridgid drill with 4 inch lazer and 6 inch laser for some time. ridgid keeps getting better so i keep buying them as does shappell so i keep spending with them as well.
if you find your under powered at all just lighten the cutting load by lifting some so it takes less material per revolution like we do with metal. times it may feel under powered might be when the ice is very wet from snow pushing the ice plate under water. also you can keep clearing the shaving out like we do with concrete and wood by lifting the bit most of the way out of the cut.
listen to the motor and bit and you'll know much more. if at any time it feels like one blade is working harder then it's time to sharpen or replace them. with lazers you can damage the angle of attack by reopening holes. it takes a long time to notice it tho.