I recently read Deathbird Stories after Neil Gaiman cited Ellison as an influence.
His more abstract concepts in Paingod and Deathbird are disturbingly relevant and in those stories you can see why Gaiman counts him as a significant influence.
I didn't realise he wrote so many scripts but it makes sense when you read something like Along the Scenic Route which comes across like a an everyday Mad Max/Deathrace experiment where armed and armoured vehicles are allowed to duel each other to the death over minor road rage incidents. Still reckon there's a movie in it (Netflix are you reading?).
It's a mixed bag but I'd recommended it if you like your sci-fi dark and pessimistic.