The 2.4L I4 didn't come until much later, not with the Rio. Some late YJs got the 4.0 I6 update though.It's been a long time but I also recall the last of the YJs(1995) getting a package that had some of the TJs improvements. I think it was called the Rio Grande and had an updated 4 cylinder and maybe a few other improvements.
Just pointing out that final year updates DO occasionally happen...
The late JKs might get the PUG, but wouldn't count on it will all the associated ECU programming required, and the transmission programming and torque lock-up converter bluntung it's benefits. The YJ and TJ shared the same transmissions unlike the JK/JL, so makes it more of a clean break, but could happen.
As for the axle, the Recon already updated that.