Nothing for us, we are for nothing fit;
Chance, or ourselves, still disproportion it.
This may be right; but after careful consideration I have retained the punctuation of 1633. In the first place, if the 1669 text be right it is not clear why the poet did not preserve the regular order:
Is man now than he was before he was.
To place 'he was' at the end of the line was in the circumstances to court ambiguity, and is not metrically requisite. In the second place, the rhetorical question asked requires an answer, and that is given most clearly by the punctuation of 1633. 'How little more, alas, is man now than [he was] before he was? He was nothing; and as for us, we are fit for nothing. Chance or ourselves still throw us out of gear with everything.' To be nothing and to be fit for nothing—there is all the difference. In the 1669 version it is not easy to see the relevance of the rhetorical question and of the line which follows: 'Nothing for us, we are for nothing fit.' This seems to introduce a new thought, a fresh antithesis. It is not quite true. A breeze would fit them very well.
The use of 'for' in 'for us', as I have taken it, is quite idiomatic:
For me, I am the mistress of my fate.
Shakespeare, Rape of Lucrece, 1021.
For the rest o' the fleet, they all have met again.