Me too, 2 more eps to go, just live with it
I don't know what otherway to say this.
You do not have to enter a font or size tag. You do not.
Notice how right there you just flat-out typed your post? Just. Do. That.
Don't assign a font, a size, or a color. You can't. When you type your post in Word or whatever just type it out and type-in the Underline/Bold/Italic tags. That's all you have to do.
You cannot change them, the board's stuck on one set of them forever. Just type your post. Simple as that and not nearly as complicated as you've been making it.
Also, the "preview post" or even the "edit post" buttons are your friends to correct these issues.