Deciding 430exII or 320ex?

Hi - I already have a 580ex I but am thinking of getting a second flash mainly for slave, for indoor or outdoor portraits. I use a 5D mark 2 and ST-E2 as control.

It is difficult to decide which to get, as they are just $30 apart.

To me, the advantage of the 320ex would be:

1) size & weight. For light travel and holiday, bringing the 580ex is a curse. I will probably bring flash more often if it is the 320ex.

2) LED light. Might be handy...perhaps as a torch or video?? Though I don't do video much.

Advantage of the 430exII are:
1) More power. But do I need it as a secondary flash??
2) Manual control
3) More coverage (24-105mm) vs 24/50mm in the 320ex.
4) AF assist light better

I would say, if I don't already have the 580ex, the 430exII is definitely more appealing to me. But for my use as a secondary, I wonder if the 320ex is "complement" me more.

Have anyone gone through the same decision process?

(I've posted this on the light/studio forum but I didn't get much response)