lol, I am picking holes in my own arguments too. I often find that I am chasing birds or wildlife and I could benefit from a weathersealed lens wider than 70, ( sometimes the 70-300 isn`t wide enough) the 24-105L would fit that spot nicely. Not really into landscape photography.
But what I need is a bit more subject isolation, f4 is sufficient for my needs from around 80 on and the 70-300L is really nice for that. I worked out that the 70-300 is a bit like a 70-200 f4. Except is has more reach and better is. I don`t need f4 at 200, there is enough dof on the 70-300L
If the 17-55 is usm was weathersealed, I would already have it. As it is not I cannot commit to it. I find it hard to scrape up the cash on the big 24-70L though, but I might end up doing that.
I can keep going around in circles
The ideal lens for me would be a weather sealed 30-130 2.8L IS USM for a cropped body.
Will I go FF?
Unlikely, in the near future, as the price of the new 5D III will be too high and the old one lacks things I want; stuff that I currently have in the 7D.