In regards to ps3 purchases and getting a discount on the ps4 version, if you have already purchased ALL the tables from season one (TOTAN to the AFM pack), a $15.00 version will show up in the PSN store as long as you're using the same user ID. That's 50% off of the regular season one set.
I do agree with the OP. I've played most of the tables last night after downloading and in "dark" mode the lighting is excellent. GI is now controlled and can be dimmed or shut off as the table ROM dictates. It doesn't go completely dark but pretty close. Flashing effects are impressive to the point that you can momentarily lose track of the ball just like IRL.
Physics are improved too. The ball feels like it has some more weight and weak ramp shots don't have that vacuum effect that has been seen before where you know the ball shouldn't make it but the ramp "pulls" it anyway.
I've played VP and FP over the years and the PS4 version of The Pinball Arcade is, by far, the best pinball simulator out there. This is NOT a straight port of the PS3 version. This had to have taken a lot of time to do. TZ was the first table I played and after seeing the GI partially shut off and move around the playfield during Powerball, I felt this was money well spent. Hell, even thirty bucks would have been nothing for all these tables (around 20, I think).