In March and April last year I spent 6 weeks driving around various parts of Europe and the UK, coming from the land of Oz I wasn't really sure what to expect so I had with me the 16-55, 10-24, 50-140, and 35 1.4, upon review of which lenses I used the most it was the 16-55 closely followed by the 10-24, I only used the 50-140 during a portrait session in the UK.
Obviously I can only speak from my experience, but I didn't find the 16-55 too big or heavy and the 2.8 certainly helped indoors. I've never owned or used the 18-55 or 18-135 so can't comment on those, but can certainly endorse the 16-55 without hesitation.
FWIW on my next trip I'll be taking the 10-24, 16-55, and 90 as a short telephoto.
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