To bust the gate in Old Soldiers you are given 111 zerglings and 36 banelings no matter which strain is chosen. If you went the swarmling route you should have 166 lings and 54 banelings. It is the same after the multi-nuke strike you are only given ten zerglings to start out with be it raptor or swarmling. As it is now raptors are better because you don’t have the right number of swarmlings. You are given 50% less to do the same job and it does not get done.
In the Enemy Within Niadra’s spawn is tied to two zerglings per supply not three as with swarmlings. With raptors chosen Niadra gets 8 supply for her first evolution and she can birth 16 zerglings. With swarmlings she is given only 10 and not 12 and the only way to get to full supply is if she can get to 20 zerglings which is 2 zerglings per supply. The math does not add up for the other two evolutions because they keep thinking two zerglings instead of three. They don’t give Niadra 50% more supply.