Quote: Sharpness: 16-45, 18-135, 18-55
The photozone numbers say different... the 16 is better wide but by 24 the 18-135 is ahead and stays ahead. I odn't know really if it's better than the 16-45, it's just really good.
My theory is have a good walk around zoom to cover as much as you can, fill in the rest with primes. Using the 18-135 and then adding primes would be the way I'd go.You have the 35 and the 70 so you're well on your way. The tested DA 16-45 CA numbers are brutal in the wide end, even by relatively brutal 18-135 and all purpose zoom lens standards. SInce it's correctable but I have no idea how that affects IQ. I really like to see some corrected images. SInce I've never noticeable had CA on my 18-135 it's never been an issue.
I have absolutely no use for the 18-55. We have 3 of them. I use them as "model lenses" on my film bodies. They make them look more like cameras in the display case. We have some great shots taken with them, but the 18-135 is just better.
Anyway I like option 3. That's a great starting combination. You can build on that. If you can keep your 50-200 until you can get something better that would be great just for the long end. It's just it's hard to find anything that's really good after 150 mm for cheap.
The 15 Ltd. to go wider than an 18-135 would be awesome. With 16 mm on your 16-45, I don't know if you'd even need it.