I plan to take my 6D and S100 as a pocketable backup. My lens choices are:
24-70 2.8 II (just purchased yesterday) - maybe...
70-300 L (offered as a loan by a friend)
... you may even wish to buy the Tamron 70-300 VC, as it isn't far off in terms of IQ but it is 1/3 the price and about half the weight (consider both hiking weight and checkin weight if you're flying.)
You may even want to consider just going with the three zooms - 24-70, 24-105 and 70-300. At a wedding, you don't want to be swapping your lens around too much otherwise you'll be missing photo ops.
For hiking in Sequoia, I'd recommend finding a tripod that weighs in at about 2.5lbs or less. Depending on which part of it you're in, you really don't want to be hauling around heavy gear as that'll mean less food/water.