No-brainer for the price/performance ratio of the 85 f1.8 lens. Just go for it - it might be a bit long for portraits on a cropped DSLR, but it is perfect for some short tele photographies of concerts or other low-light situations. On full-frame it is the ideal portrait lens IMO. It complements my 70-200 f4 IS lens perfectly.
yeah, I'd say get a 50 first. 50/1.8 gets my vote, but the 50/1.4 is also good. I'd also get the 100/2 over the 85/1.8. I wouldn't get the 100 macro unless you really want a macro lens... and then I would look at all the other options as well.
I'd consider a fast 50 first to complement your existing lens kit. On a crop body, I personally find the 85 and 100 a bit long for indoor candids and portraits, and prefer the 50-60mm range. The 50 on APS-C will give you portraits with less flattening of features; it draws with an "intimate" look that I quite like. I don't think it's overkill to have both this and the 30.
If you go that route, the Canon 50 1.8 is cheap and optically good; the 50 1.4 is better if you can afford it. The new Tamron 60mm f/2.0 macro may be an interesting choice if it proves it can double as a fast portrait lens.
The longer primes can be great for sports, stage, and other uses, or for portraits you like the flattening; it just depends on what you shoot.
