And because of this, would the above scheme be better off using different wallets rather than different addresses within the wallets?
That depends on what you are trying to accomplish. When you send bitcoins from an Electrum wallet, you will not be able to choose which bitcoins are sent. The wallet will decide for you from among all the bitcoins in the entire wallet.
If you freeze (right mouse button context menu) all but one address than Electrum will only send from that address.