^The exploding head was a one time occurance and might actually been an experiment to move TNG into a more "mature"/"action" direction which obviously did not pay off (for whatever reason)
Actually I have some information on this that I got from the research and interviews on Mission Log of people who were there for the making of this episode.
Mission Log Podcast: a weekly podcast that's mission is to go through the entire Trek universe, in order, with discussion, researched trivia, interviews with people involved, found actual documents posted on their site, messages, meanings. (except they are still considering how to do the DS9/Voyager overlap

)
So here is what I learned about the
Conspiracy exploding gore thing:
-GeneR was still stinging from lack of creative control with TOS. And not as simplistic as ego either, the TOS thing took him down health wise, emotionally, and had impacted his family life. TOS was major trauma for him.
-He now has agreed to do TNG with contract signed 'total' creative control for the series.
-A network or studio guy (named in the podcast) made a note to Gene that that scene in
Conspiracy needed toning down a bit.
-So Gene had production ratchet it up a bit.
-Another note from studio or network guy
-Gene does the opposite and ratchets it up again.
-I forget how many repeats of this there were but enough that people in Gene's production side were concerned.
In the end:
-Gene has
Conspiracy alien gore/whatever to giant BIG (for the time) for what he recognizes is a 'Don't Cross This Line' interference from studio or network. And he is making a giant BIG statement to them.
-the studio or network guy apologizes for overstepping Gene's contracted control & says it will never happen again.
-asks him to put
Conspiracy back to what it was before he intruded
-Gene ignores this and airs the biggest baddest version (for its time)
Conspiracy has gotten to in this power play.
And we get our first (and maybe only?) Trek episode to come with a viewer or parental warning before it starts.
And while Gene held personal control of TNG nobody from the studio or network crossed the 'Don't Cross This Line' again.
Right. So here's the catch; I can not remember if this information came in
-Supplemental #014: Richard Arnold
--or--
-the
Conspiracy podcast #120
--or--
-a different supplemental podcast.
Sorry.
I'm leaning toward Richard Arnold because he was there for all this and I am remembering 'someone' being interviewed on Mission Log, telling this story first hand because they were there and witnessing all of this.