For a start all receivers register with different precentages so that means nothing. 3863 is the strongest TP though and 3716 and 3743 are about the same.
Variances due to heat, size of dish, terrrestrial intereference and other factors need to be taken into account.
But yes the difference would suggest you LNB is not tuned correctly. Tweaking the LNB may increase your weakest freqs. The highest ones may drop a bit but the main point is to have the weakest freqs tuned to the max as the others are already above these.