Change or keep??

So I have ordered the 24-70 MkII and upon recieving I will be in a quandary. I have shot a few weddings and the 24/70 was my second shooters lens. I found that I need more flexibility so I picked up the new version to get the 50 prime off my camera. I am considering trading or selling the MK I and funding a 24-105 as a replacement and general purpose lens. The other issue is what to do with my 24 MKII 1.4. I never found the magic it is purported to have and I feel as though I can get by with my 24/70 for the wide shots as needed.

So should the 24/105 F4 IS be a good lens for a 2nd shooter that has the ISO cranked as needed. Also will be general purpose vacationing option.

Would you get the 35L/S35 instead of the 24L or use that to get to a 16-35 and part with my 17-40?

Ideas? Thanks!

Sorry, another was to Keep both versions and the prime.

I'm a fan of the 24-105 mostly for its versatility. I don't find the f/4 limiting very often.

Thanks for the info.