Lot of newbie questions

Hello,
I am new here and new to coding SVG (used inkscape for a longer time; not new to XML).
My main ressources where "SVG Essentials" from 2002, the "SVG primer" at w3.org and a bunch of links.

And it's not clear if I should ask my newbie questions here - please shove me to a more appropriate forum then.

Questions:
1. processing.org vs. SVG
I want to code my artwork (excessive patterns) with a few animations and some interactivity for changing color etc. with SVG and pure as possible SMIL, and only if really necessary a little bit JavaScript or XSLT.
From a processing view - where are the greatest limits of SVG?

2. BestPractice today from w3.org with attribute, style inTag inHead and extern?
I stumbled upon a view recommendations in the innernets, to make ugly things with the presentation layer but would prefer the pure separation like in good XHTML-code. What is todays w3.org-BP for SVG styling?

2.1 Did I get that wrong, that there are some SVG presentation attributes, that I could not address with CSS (If so, is there a comparing list somewhere?) Couldn't find this source again. Or otherway around: Could I style every attribute via CSS-Style (yes, I understand, that there are also SVG CSS-styles that are not available for XHTML)? 

3. relative line with angle:
Could I draw a relative line +10px _with 60 degree angle_ and/or do this in a polygon for a triangle? I couldn't find anything - maybe wrong search-words?

4. copycat prevent
Is there any other way to hide the sourcecode of a big lossless scaleable (and therefore printable with high resolution) artwork instead of showing it only as a filmed video?

ThanksInAdvance
bert