For example we know it's a bad idea to stream from the PC (on wifi) to the TV (on wifi.) Why that is, is well discussed. We also know why we want WPA2-PSK or AES without hiding the SSID and other things noted in the CNET Networking forum.

Since WiFi is subject to interference no matter the distance, no matter will guarantee it works today. But there are things we can do to improve streaming.