‘As for me, I shall behold your face in righteousness,
I shall be satisfied, when I awake, with your form (likeness).'
In contrast to his enemies the psalmist beholds YHWH's face ‘in righteousness'. This may mean that it is because God has accounted him as righteous in that he has responded to Him truly under the covenant, including the necessary making of atonement, or because he sees YHWH as the Righteous One. Either way he considers that to see the face of YHWH is better by far than all that the unrighteous can have.
‘I shall be satisfied, when I awake, with your form.' When he wakes he will be satisfied if he but behold the ‘form' of YHWH, as Moses had done before him (Exodus 33:17-23). What are the treasures of earth beside this? His only desire is to live for YHWH and enjoy His presence and see His face.
It is quite probable that we are to see in this his conscious hope of living on for ever in the presence of God (compare Psalms 16:9-11). The point is that the unrighteous live on in their children, and maintain their treasures by passing them on, while he lives on in beholding YHWH continually and his continuing treasure is found in YHWH. He needs no children or children's children in order to be fulfilled because he will find his continual fulfilment in God. And God is his eternal treasure. In his times of ecstasy at least he cannot conceive of being separated from God by anything, not even by death.
‘When I awake.' Probably not from the sleep of death, for that is a much later concept, but from the sleep of half-realisation of YHWH to being awake to the full realisation. He is confident that one day he will see Him as He is (1 John 3:1-3). That is all that he desires.