I was pleasantly surprised by SFStL this year too. They've made tremendous strides with both trees and visual improvements around the park. The wooden coasters are a tremendous trio of three different schools of design, and of course the Batman and Freeze clones are always good. It's still Six Flags, and there's still a ton of tacky stuff around that simply doesn't need to be as tacky as it is, but overall it all works well if you are just there to ride rides.
You'll hear a lot of criticism on this board for SFStL, but you have to understand a lot of the people here aren't coaster enthusiasts and are looking for more in a park. The vast majority of parks these days offer virtually the same experiences, just with different rides. The driving force behind this board is that SDC is different to various degrees, and there's a lot of fan resistance towards being more like other parks (SFStL usually being the prime example). SFStL is great for what it is, but you have to be willing to put up with what comes with the SF experience.
What drives most people on here nuts about it is that there are a lot of little things SF could do differently that would make the experience much more enjoyable, but that would cut into their profits without much ROI, so they'll never do them. They're overtly focused on wringing money out of people's pockets while keeping expenses as low as possible, just like most theme parks. It gets tiring after awhile - at least SDC is much less overt about it. It's like a resort vs. carnival mentality.
Could the Justice League ride be a sign of SF stepping up their game though? So many of their parks have gotten huge, to the point where they could easily become sustaining resort properties, but SF has kept their model consistent no matter what. Focusing on higher quality rides would be a first step towards that though.