If you're REALLY REALLY into Portraits, I'd say consider the 35 f/2, 50 1.8 and 85 f/1.8.
If you want a 50 1.4, I'd go with the Sigma over the Canon one - despite my personal like for Canon glass over 3rd party. You could always consider the Sigma 85 1.4 as well.
While my personal preference is for zooms as general purpose lenses for daily use, if you're using it mostly for portraits, you wouldn't need quite that versatility that wedding/event photographers need.
If you've got the cash, the L lenses at those focal lengths are extremely tempting. Don't try unless you intend to buy, you'll find yourself wishing you had it.
the 70-200 f/4 L is a nice addition though. But if you don't shoot at long focal lengths a lot, and shoot mostly outdoors in good light, might I suggest the 55-250 EF-s? Cheap as chips, and good value for the money. Nowhere near the L's in IQ, unfortunately, but for the price you pay...
The 17-55 EF-s is really really nice, but if you were to shoot mainly portraits, you might just find it a touch lacking - still a good choice as a general lens though