this is pretty much exactly what i do, i run a base 4-3 with a Balanced SS or FS set to the depth chart as my LOLB and i make sure that my ROLB is a good coverage backer and my MLB is a Run Stopper, its a total lock down D and its basically a 4-2-5 without the glitchy DB getting stuck on the D-Line. Although this is kinda opening my eyes to even more options with the 4-4 defense aswell i currently don't use it, but i may now