I started to read the documentation on the KOMA Script classes because they seem to have many tools that are more flexible to use than the standard classes, But I don't understand where to put all the options. Is within \documentclass the best place, or not?
By example:
\documentclass[headsepline=true,paper=letter,headings=small,DIV=10]{scrbook}
\usepackage{typearea}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{bera}
\usepackage[berasans]{quotchap}
\usepackage[nouppercase]{scrpage2}
\pagestyle{scrheadings}
\usepackage{blindtext}
\begin{document}
\Blinddocument
\end{document}
This compiles well but the headsepline doesn't appear, and also the heading size doesn't change. If the class options are not the best place for it, where or how can I add these optional values?
On the other hand, regarding fonts, KOMA Script uses a sans serif for headings and other stuff, and serif fonts for text. After reading this: How to set a document for use with the Bera fonts instead the default fonts? I understand that if I want to use LaTeX fonts (without XeTeX) I need to load the page of each font and then KOMA will use them. Am I right? [In the example I use bera fonts because the package include both fonts.]