The motherboard decides how many features you get. Like how many expansion slots, storage slots, memory slots, cpu support, wifi/bluetooth, how many onboard io ports, oc capability etc etc.
So if you have a motherboard now and you don't need anything extra, like on of the things i mentioned, then upgrading the motherboard would be for nothing. It is required to upgrade the motherboard if your cpu has another socket.
So stick with your mobo, unless you upgrade the cpu to another socket one.