How can I open a new customized (color, font, etc.) Terminal window from the command line?
CMD+n opens a new terminal window.
CMD+t opens a new terminal tab.
If you want to open something other than the default Terminal, use the techniques here to open a pre-defined Terminal setup. You can also do CMD+n,i,Tab to bring up the Inspector, then use up/down arrows, or type the names, which lets you choose a pre-defined Terminal.
If you want a setup hard-coded and not yet known to Terminal.app, follow these instructions.