I don't really do cold starts (maybe 2-3 a year), but I always keep a cord of pine ready to go.
Not only is it great for short hot fires, but it's good filler wood if you get behind on your hardwoods (ready in just 1 year), and it's also great if you end up with a stove full of hardwood coals (lay some tiny pine splits on top, burn on high).
I think I heat a lot more effectively with a mix of hardwood and softwood in the toolbox.
Be careful scrounging dead standing softwood, they turn into sponges (and usually right at the base where the ants got at them) faster than you'd think.