Quick Strength up strategy for current 0.7.3 build:
Just dominate "The Bind". Do this over and over and you can easily gain over 300+ strength. (Easy damage.)
With the new limiters in place, you won't have to worry about getting too big anymore either. But when you up the limiters, it's instant growth. Except for height.
If you take the other path with The Bind, you get an EXP booster. Good for first runs.
I think the limit for either perk is 10.
With all that extra power, you should grow easily with the Growth Sigil from Torgar.
Also, you should be able to one shot basically everything.