I'll try to answer a few of your questions, at least to my limited abilities...
Teamwork: I am a one person office, so I can't help you here.
Favorites: There is not much in organizational tools for favorites - you need to create a naming convention that will group your favorites together as you would like to see them. Also you can select an option which will only display favorites of the active tool. Another way to organize the favorites is to have separate favorites sets for various disciplines, i.e. civil, building, electrical...
Layout Book: you are already doing the smart thing by putting everything on the archicad layer. I know there are some wish list postings for layout layer controls. Personally, I am happy with just putting everything on the archicad layer, if I put it on the layout, I want to see it and I want it to print.
Multiple element selections: I might be wrong about this, but I think the tabbing selection order relates to the display order. However it also depends on which tool is active, if you are on the line tool, selections will go to the line first, if you are on the fill tool, selections will go to the fills first.
Dimension Text: As far as I know, you have to select each dim. text to change it. You can have selected multiple dim texts, then change them all at once though.
Markers: They are library parts, but they won't appear under the library window with the object tool. There are a couple of ways to have your settings applied quickly. Easiest is to set up a marker the way you want it, then save it as a favorite. Another way would be by creating a dummy marker that you leave off to the side - like in the visual legend idea ( a good alternative to favorites too, see
http://www.aecbytes.com/tipsandtricks/2006/issue13-archicad.html ) Or if you are brave and know some GDL, you can place a marker and do the open object command, but I would make sure you save it a new file, I have done with with some success (and alit of trial & error), so you definitely don't need to be an expert, but this is probably only worth it if you want to change the graphic appearance of the marker.
Master file: I'm not sure exactly what you are going for here, but here is how I have set things up for myself. I have created a startup file with all my typical stories / elevations / sections ..... already set up with the markers already on the drawings, and hotspots indicating where it will line up on the layout sheet. For details I have a separate detail plan file, with my most of my details, when the time comes, I simply copy and paste the desired detail from the archive into the current project. This system works well for me. I don't have standard details that go into every project, but if I did, I would put those into the project startup file.
I hope that helps.