PS Store is on sale right now. Refer to this thread if you want to know what's on sale https://forums.dovetailgames.com/threads/play-station-sale-now-on.52870/
March Madness isn’t possible on console due to the different platforms having different requirements and opportunities for sales but as stated above there is quite an extensive sale on for PS players right now with some comparable discounts for TSW2 DLC.
I am pretty happy with the PSN sales. They come around often enough if you are patient. Bought the game for £4.99 in the Christmas sales. Thought if I don't get on with it, I've lost a fiver. Spent about £60 on DLC since. Pretty sure ECW was £3.74 or something daft in the January sale. I Initially bought NTP, GWE, ECW, TV, WS and heavy freight pack. Picked up SEHS and London Commuter yesterday. What's not to like? If you buy discounted PSN top-ups, and are on PS+, the discounts can get work out really substantial.
Some of the dlc is already half off on the in game page. Is there an additional discount for PS+ subscribers?
You get and extra 5% of anything in this sale if you are PS subscriber. Probably not worth signing up if you don't already but a nice bonus if you do. Doesn't happen in even sale but great when it does. It also grants you the launch discount if there is one (every TSW 2 DLC has so far, up to, but not including, Harlem).
I picked up the 1938 stock DLC and the Hauptstrecke Hamburg - Lubeck at a great price. I had been thinking of getting them for a while especially when in a sale but have always ended up deciding against them in the past. But yesterday I thought sod it they are cheap enough so not much lost if as suspected I find them not worth getting, not that I can afford to throw money away. But I am very pleased with both purchases, they are both great and well worth the money I paid.