new Lens???

I am looking for a "portrait" type lens. I am debating between several options. First, my current line up:
17-40L
50 f1.4
85 f1.8
60 f2.8
24-105L
100-400L

My Primary focus is portraiture and wildlife. I would like to know what my next step should be for a portrait lens. I am currently considering 200 f2.8L, 70 - 200 L either f/4, or f/2.8 non-is.

oh and 7d is the body

70-200 MK II

Unless you need the 2.8 the f4 is is a cracking lens, sharper than the 2.8 and is a lot lighter meaning you will be more likely to take it out. Handholding I imagine you would get the same shutter speed with the IS as you would with the 2.8.

Another option would be to sell the 100-400 and go for a 2.8 is mkII and x2 extender meaning you have the best of both worlds. This is what I did. with the x2 prefer it to the 100-400 focussing is slightly faster and you have the best of the 70-200 with is and 2.8. It is a bit bigger and heavier than the f4 is which is the only downside

I strobe a lot for my portraits, so not sure f2.8 is the most critical quality in the lens. I am reluctant to replace my 100 - 400 because I like the range it gives me. what about the 200 f2.8l??

Sigma 70-200 2.8 OS or 70-200 2.8 IS II. Sigma is around $1300 and is right behind the IS II and many claim it's equivalent to the F4 IS when stopped down to F4.

100 2.8L is a great portrait lens and you also get marco abilities which you don't have at the moment (and you might not want either...)
EDIT: sorry I didn't see the 60mm but it's still a great lens