This is the character I'm designing.
One hand - 10 (dual wield daggers and swords)
Archery - 13 (steady aim, power shot, eagle eye)
Illusion - 3 (just enough for invis to vanish when outnumbered)
Light armour - 3
Sneak - 8 (assassins blade, muffled mov)
Alchemy - 7 (poisons)
Lockpick - 2
Conjuration - 4 (just enough to help out a bit)
I think this build will work just fine. Invis is a must. Conjuration is good for distraction.