The assumption that some hands are stronger than others may be right, but you can lose with any hand against 72 offsuit or 92 o/s depending on the board.
Handstrength is depending on the board that falls to your feet.
A board like 772KA (or any other combo with starting trips) will not help AK,Ax,KQ to Kx and so on. The cases are rare but they exist.
I consider any starting hand except pairs as weak (even 27 or 92, recommended in special situations) because they have to hit or connect to the board. Improved (top) pairs are mostly great if the board is not to draw heavy.
So there is really no hand for me that I really love to play preflop except AA KK, rest is always a hard decission.