welcome leabit,
I have been doing a bunch of homework on laminations as that is where I want my penmaking to drift toward for now.
First there are many books available on segmented turning. these or toher info on that subject are very helpful for getting a grip on the directions for a specific design. many of the complicated looking designs are actually much easier then they look like they would be. it is a matter of gluing together one large piece then re cutting it and reorienting the pieces. this is how most herringbone and other designs are achieved. the other bid rip I have found is a 45 degree angle is not very flattering. stay either small or greater than that. follow the angles used in the designs you see and like and it will help norrow the choices for you. even a degree of angle can make a difference.
next is the knowledge of contrast, balance and complementary combinations of woods. a design that falls flat with two particular woods will pop alive with anouther selection. this is an art in itself and again best nailed down by looking at what you like and keeping your combinations at least close to that.
a last note, after all the slicing and glueing and reslicing etc. be prepaired to make an exact dead on and straight hole through that blank. you will also be trimming the blank for the barrel to a pretty exact location as well. it takes penturning into that realm of "Exactly what I intended to do" for me.
good luck
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