sketching assumptions - some relations don't show.

Hi all,

I think I know that my answer is "no", but I still have some hope...

Can you control or customize the assumptions and application of sketcher relations?

examples:

If I'm sketching multiple circles of the same diameter, sketcher currently does not snap to the already existing circle's diameter.  Applying the "equal to" relation would same some time - can it be done?

If I am sketching some symetric geometry and I put in a construction line for symetry, sketcher currently does not snap to symetric.  This also would save some time - can it be done?

Are there other time saving tricks that you might know of for sketching?  I saw a demo once where the presenter "rectangle / window - selected" many circles and aligned them all vertically.  I have tried this several times and cannot get it to work.  I always need to select the center points manually and then apply the relation.  What am I missing?

I would love to see a cheat sheet for tricks and tips like this. 

e.g. - hold down the shift key when you want to dimension to the tangent of an arc...  Those kick-ass time savers that are "right at my finger tips" but I don't have the knowlege.

Thanks a lot!

-Nate

SolidworksSketching