Replace the 75-300 with a 70-300L - will be better for journalism
Brian, what is your take on 70-300 L vs 100-400 L?
37.1 oz vs 48.7 oz is really the big camera-tipperhttp://www.the-digital-picture.com/Reviews/Canon-EF-70-300mm-f-4-5.6-IS-L-USM-Lens-Review.aspx
To the o.p., sooner or later, a good tripod is needed, and usually you don't know it until someone strong-arms you into doing it right
Maybe not for some journalism, but events, definitely makes a difference.
What I ended up with:
Manfrotto 055CXPRO4, Manfrotto 468MG and converted the ball-head to an arca-swiss type . . . at the time I got the pair for $454 and there was a rebate on it.
I really don't hesitate to take it along if I even *think* I'm going to need it, since it's so light and hassle free to set up/take down.
As for lenses, if I had to own one lens on a crop body, it'd be the 15-85mm, which pretty much stays on my 60D now that I have a 5DmkII. As long as my head is on straight, I can't take a bad
picture with it. The 24-105 you mentioned is also a good choice, but the extra-wideness of the '15' in tight spaces sometimes makes a difference.