I agree with Roco that Overwatch is one of the best PS games I've ever played. Especially if you're into shooters where it's not just about shooting. The MOBA/teamwork tactical aspect of it and different heroes with different abilities makes for a lot of very unique games. It is the best when played with a group of friends on your team though, as communication is the key to success.

My PSN ID is TheEndless7 if anyone ever wants to add me.

PSNow and PSVUe are two different things. I've used both. PSVUE is a cable TV alternative with a bunch of non local channels. It seems decent. But I have nothing to compare it to. It's completely different from the FIRETV box I have, although I can stream PSVUE through the Firetv. I honestly use it mostly because it was the cheapest way I could get the racing and hockey channels I wanted with little extra. Right now for like 55$/month you can get like 100 channels INCLUDING HBO, showtime,and the NFL network. And there are various packages below that. The user interface is not very good and a pain to navigate. But the video quality has always been good. While you do get the local fox sports affiliate, you do not get any local channels. ((Although it does give you ABC/NBC/FOX on demand)) SO you need an internal dish for things like the Packers.

PSNOW is a streaming video game service that offers around 150ish PS3 titles to stream on your PS4. It works pretty well, but if your connection isn't strong it's prone to skip and lag a bit. Usually nothing that pausing the game and waiting a few moments wont fix. It does have some great titles on it like Red Dead Redemption and all the Borderlands game and I think every Telltale game. It's a bit pricey for what you get. Buying it for a month here or there to beat a couple of the games that come on monthly may be worth it. The library has been expanding more in the last few months than it seems like it did all of last year. So I'm hoping they add in even more.

I'd like to see PS1 and PS2 games added to but i have no idea how feasible that is.

Steam is just essentially a digital retailer of video games. You can log into their store and buy games to download and play. You can also set up friend lists and see what friends are playing and if, say, they're in a game of Battlefield you'll have the option to join them. They do offer a lot of great sales here and there but it tends to mostly be on older stuff.