I'm joining you too.
I did like Season 4.
Sure I did miss Valerie and Libby, but I think it was a good idea for Sabrina to have a witch friend of her age and rely on her when she had trouble with her magic, but perhaps they could have given Dreama a little more participation.
Brad was interesting and had a lot of potential, but again, they didn't give him enough screen time to develop the character.
I think in this season, it's where we see a more maturing Harvey/Sabrina relationship, more than just teen love, which I loved, except the part where Sabrina cheated on with Josh.
Josh is probably the negative side that I see of this season. His introduction was annoying to watch and can't simply accept him, even they soften him up on the next seasons, can't bear he was a major factor on Sabrina/Harvey breakup, and a negative point to the show's decline in ratings and audience, as well as other factors.
And just as you point out, I wonder how ABC would had handled the 5th season.