4 speed harder to get in get after warmed

Sounds like it needs a bit more plate departure.
The steel washer idea is a good one, but must be executed properly. Chrysler used to make a kit, with a steel swivel.
The rubber isolator deal isnt the best idea. It seems to work ok when new, on a non-performance application.
If you havent yet done it, Figure out a way to keep that adjuster nut from backing off and losing its adjustment. On my steel swivel, I put a nut on both sides of the swivel. After the adjustment id done, I lock it down with the rear nut. At the end of the adjuster rod, I drilled a hole and put a cotter pin in it. I dont lose my nuts anymore.
The free-play is often cited as being 1 inch. That is to say; the first inch of clutch pedal travel does nothing but move the release bearing out to contact the clutch release fingers. Thats ok for a DD. Just make sure it actually releases the clutch and doesnt grind going into Low/rev. And you shouldnt have to push it all the way to the floor.
I set mine up a lot higher. It just means adjusting it more often.