To change the default size and anchor-point of all new text, use the "Text" preferences (in menu File / Preferences..., "Display" section, "Text" tab). The top part of the dialog determines which types of text will be affected. The middle part lets you control how that type of text will appear in the future. You can set the size, anchor-point, font, and style.

Below the "Default Text Style" section is a popup that sets the default font for Electric. Below that is a setting for the "Global text scale". Normally, all text is drawn at 100% of its stated size. However, you can globally scale all text by typing a value other than 100 into this field. You can also use the Increase All Text Size and Decrease All Text Size commands (in menu Edit / Text) to change this value, and alter the size of all displayed text.

The bottom part of the dialog controls "smart placement" of text, which adjusts the grab point according to the environment of the text. This currently applies only to export names, which are placed relative to the arc connecting to the exported node. For example, if a node on the left end of a wire has an export, and the "Horizontal" placement is set to "Inside", then the export text will attach on the left side, causing the label to appear inside of the wire.