Another favorite in wedding work is leather leaf fern. It's inexpensive and fills in an arrangement quickly.
Set aside your shorter pieces for bouquet and corsage work and use your longer pieces for your bigger florals.
Again, work from the sides, straight in at first and then angling upwards.
You want your final greened piece to be all around and filled in evenly.
Having greenery come straight out will give dimensional look from a distance. All of it angling upward will give it a rather "flat" look.