Please do tell how? Everything that made it to screen had to have his approval.
He was awful to all the women actors, corroborated by Denise Crosby, Marina Sirtis, Terry Farrell, Jeri Ryan.
He gave them zero respect during contract negotiations, increasingly wanted to sexualize their roles (catsuits, "decontamination" scenes, etc), and straight up fired Terry Farrell from DS9 after she just asked for an episode reduction for S7.
He screwed over Wil Wheaton by forcing him to turn down an opportunity to star in a big movie for no reason other than control/power
He denied Garrett Wang the opportunity to direct an episode of Voyager, even after a bunch of main Trek actors have directed episodes before.
Yeah, screw the only Asian Actor on the show, that's a great look Rick.
The Constant Reseting of Voyager's Condition to be back to normal at the end of every episode so that it would help with Syndication.
The Year of Hell was supposed to last all season as a Season long arc.
It got cut down to 2 eps because of Rick Berman not a fan of Serialized Story Telling and wanting it to be shorter, MUCH shorter.
Rick Berman in general hated Serialized Story Telling, only cared about independent self contained eps so he could syndicate the shows.
The DS9 crew had to go behind Rick's back to get their Story Arcs told the way they wanted to.
He told the human actors on VOY to *intentionally* be boring so that the alien actors would seem more realistic. Numerous scenes had to be reshot because the humans seemed too emotional.
He fired TNG composer Ron Jones midway through the show's run because his music was "too noticeable" and he just wanted "wallpaper music".
Pretty much all of the good early TNG music is from Ron Jones, he was excellent.
Increasingly stuck his nose in the writing credits for VOY and ENT (even though he wasn't a writer!) as the franchise began to spiral downward.
Once he gave showrunning control over to Manny Coto for S4 of ENT, the show became good, although by then it was too late.
That's just one of many issues with Rick Berman.
His job was to run the franchise, keep it on time and on budget. He did that in spades, or else Paramount wouldn't have kept bringing him back.
As far as creative decisions go, please name someone who has a perfect track record?
Perfect, I don't believe in Perfect.
But JMS (J. Michael Stracynski) handled B5 a bit better.
And that was a contemporary of Berman Trek.