A few thoughts on this.
It wasnt that they had a bad strategy. Its that for essentially the first year or more there was NO single overall strategy. Davis was simply trying to beat off the early Union forays and establish borders while building an army and government. And even once that was done the CSA was still hurt by State's Rights and their bleeding of resources, from Georgia, and SC. in particular. Politically also they were tied only to the idea of winning their independence and moving on, there was no interest or desire for conquering Norther territory, outside of maybe the Border States.
There really wasnt any other strategy that would work. Bold aggressive defense was the only way to try to break Union morale and force a political solution. Whenever the CSA got into trading body for body, or stuck in a siege things got bad. But by striking Union forces whenever possible if they were divided or where they werent expected was really the only shot.
The problem then becomes that after about 1862 that wasnt possible int he West as points like Vicksburg simply could not be lost, same later with Atlanta, and that the North could simply replace men more easily. thus in the East Lee was forced to act even bolder leading to his Invasions. The first actually was an interesting idea as there had been noticeable Confederate sympathy in Maryland in 1860/61, but it never panned out. The other was born almost of desperation to try to relieve stress in Virginia and hopefully create opportunities for victory by maneuvering.
So I would say your premise is faulty/wrong. The CSA did more or less the only thing they could. Strategic defense with aggressive bold strikes on enemy forces when possible.
In all honesty the South was hurting from Day #1. And was almost assured to lose when Fortress Monroe remained in Union hands (blocking access to the Chesapeake. And New Orleans fell early in the war sealing the Mississippi.
What sort of stuff have you read/ think about it, I would love to recommend some books!