I'm not an expert, but let me suggest a semi-hyperliteral translation
such as the following:
"Now it happened during the being baptized [of] all the people,
[on] Jesus also being baptized and praying, [for] the sky to
be opened and the Sacred Spirit to come down on him in a bodily form
like a dove."
Alternatively, I sometimes find it useful to treat a NT Greek
infinitive as an English gerund -- in fact, this is what I
usually do when the infinitive is qualified by a definite
article. Hence, something like
"Now during the being baptized of all the people, [with] Jesus
too being baptized and praying, [there] occurred an opening
[of] the sky and a coming down [of] the Sacred Spirit on him
in a bodily form like a dove."
That is, the EGENETO goes with the latter infinitives, and
what comes in between are qualifying phrases.
On EUDOKEW, I have not been satisfied with the usual interpretation
as "I am well-pleased". Given some other NT contexts, the happiest
I have been is something like "I am setting in motion a kindly purpose."
In this context, if we interpret EN as a preposition of agency,
we could interpret EN SOI EUDOKHSA as "by means of you I (have)
set in motion a kindly purpose."
Cf. the use of EUDOKIA in Matt. 11.26,
hOTI hOUTWS EUDOKIA EGENETO EMPROSQEN SOU
that in this way a kindly purpose came into being
(was realized?) in your presence.