I carried a Remington Sendero in 300WM this past Oct. at 10,700' for 5 days and wouldn't trade it for anything. The rifle weight is grossly overstated when you think about it. I also carried a 35 lb pack on external frame so how would 1 1/2 lbs more in a rifle mean anything other than a better shooting platform? Druthers and I would prefer a heavier rifle for off hand shooting any day of week. Recoil is obviously less as well. Heck, my lunch weighs in over 5 lbs

I believe the heavier rifles will definitely shoot better over most conditions so I wouldn't even think about it. If the extra weight is that big of a deal then you didn't physically prepare for the hunt anyway. Buy a good sling and don't even give the weight a second thought. Most of time you are still hunting and tend to rest the rifle against something anyway. Did you ever carry a Hawkins all day? Modern rifles seem like a powder puff in comparison.
Muddyboots
PS - If you reload, I'd measure the throat on the Tikka before you buy it to make sure it will allow you the cartridge COL that you may desire off the lands. I just bought one in 300 WSM and it is long throated to such an extent that I cannot seat 165 gr. bullets 0.010 off lands and still meet one diameter in case. 150 gr. bullets will be so far off the lands they will have to be timed by a calendar to reach them... :-D
I'd be curious where you found this Tikka so I can contact them for 300WM in same rifle.
Thanks,
Muddyboots