I would suggest doing one pull per station,with two cables of Cat5e.
You can use either for your voice, but you did not say if your voice connections require any special connections,such as one pair,two pair,etc,or if this will be a VIOP.
I would put them all on a data patch panel and number them 1,2,3,etc and at both ends, and then use which ever one I desired for the voice by using patch cords of different colors (ie: blue for data, white for voice).
In areas where there may be an additional device,such as for a fax or printer, I would run a third cable for that location.
You can seperate the cabling at the rack for either a data panel or a voice panel or even to seperate racks, that is your call.
For connections of the analog lines (like for fax) I would run a tie cable from the voice backboard to a seperate patch panel on the rack and color code those connections with another patch cord ( ie: yellow for analog lines).
Good Luck
Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.
Also a General Class Amatuer Radio Operator.