Perhaps it would be more instructive to consider it in terms of percentage:
So, as a percentage the death rate was about equal? By that standard, it would be legitimate to shoot one innocent bystander for every criminal we have to shoot? For every second flight across the ocean we crash one plane? For every second trip to the 7-11 we wreck one car?
Even after secession, the issue of what would happen in the territories and what was to happen to runaway slaves was probably going to lead to shooting.
What led inevitably to shooting, in my humble Canadian opinion, was the fact that the states had their own armies ("militias"). In Canada, the provinces can disagree "violently" with the federal government or with each other but they can't do anything about it.
Maybe the Civil War was God's punishment for having a flawed constitution.