After a successful port to CMake, the next step should be to localize the scope of targets and variables even further: consider moving options, targets, and variables closer to where they are used and modified. Avoid global variables since they will enforce an order to CMake commands, and this order may not be evident and will lead to a brittle CMake code. One approach to enforcing the separation of variable scopes is to divide larger projects into CMake projects, which are composed using the superbuild pattern (see Chapter 8, The Superbuild Pattern). Consider splitting large CMakeLists.txt files into smaller modules.
The next steps can be to test the configuration and compilation on other platforms and operating systems in order to generalize and bullet-proof the CMake code and make it more portable.
Finally, when migrating projects to a new build framework, the...