I also felt like I had to put a bit more effort into pushing?? Because it's "soft", there's less to push against?
Sounds like it was too soft. When you push against the ice, ideally, you want as much of the force you exert on the ice to result in a return force propelling you into motion. When the ice is soft, part of the force you exert is used to dig the blade deeper into the ice and then to compact the ice, so you get a weaker return propelling force. At the same time, the friction on the skating blade is higher with soft ice, so you have to push even harder to get a decent glide. When I practice Figure-8's on hard ice, I have no problems at all completing a whole circle on a single push; but on soft ice, it's a struggle.