Based on your descriptions your internet sounds to be about the same speed as mine. Yes, you will have to be patient with downloads as maps take up a lot of room, the new campaign has 29 missions and each uses a unique map.
Anyways point being my slow internet isn't much of a bottleneck when actually playing, ZK is pretty bandwidth efficient and doesn't require fast ping. Assuming you have a nice GPU (amd or nvidia) and you can wait for all the content you should be able to play fine.