Yes, Crisis would be a good next step. I think it'll have to wait a bit though. JL is a two-parter at least and from rumors and such, check out the details in the JL1/2 thread under speculation, I think it will be:
JL1 - Death of Superman.
JL2 - World Without Superman
JL3 - Return of Superman.
The whole DOS comic arc set over 3 JL films.
um did you not see Batman v Superman. Superman died at the end of the film. Their not going to bring him back in to life in Justice League then kill him again and bring him back in Justice League 2. That would be utterly dumb.
This is one big grips I had with Batman v Superman and them pulling out Doomsday and killing Superman. First off they did a piss poor job of portraying Doomsday. They should saved him for a solo Superman film and did it right. I didn't have problem with Lex creating Doomsday. I think that would worked fantastically in a solo Superman film.
Second Batman v Superman was Stupid in that every one hated Superman through out the whole film. Then he gets knocked off and suddenly the world is grieve for him; give me a break. That's piss poor writing.
Also by killing him off and then bring him back in Justice League you ruin a great opportunity to show his death has on world. You do this by showing moments through other DCMU where guys like Flash show how much loosing Superman hurts and effects the. You basically do a World With out Superman in the other DC films. Then you bring him back in Justice League. However DC couldn't hold their wad and use that and wasted the opportunity.
All they did with Batman v Superman was give comic book fans everything they think we wanted. Now I'm sorry I want all those things but one I don't want it for sake of it. I want it done and done right not half ass which is exactly what they did.
The fight between Superman and Doomsday was epic beyond words. Doomsday just basically went in a tore apart everything in his path and then beat the living snot out Superman just for kicks. It took every ounce of energy to defeat him. The final moments of that fight was epic. Those two where hitting each other so hard that the concussion from their blows was shattering glass windows from buidlings. It was a knock down dredge out slug feast. What did we get for Doomsday Wonder-Women and Batman trying to fight him and then Superman spearing him and getting impaled in process; lame.
Also Batman and Wonder-Women would had no chance of remotely going toe to toe with Doomsday. In fact recently Wonder-Women though she could handle Doomsday and very quickly realize she was out of her depth and ran. That's how bad ass Doomsday is. We got stuck with a weak piss ant version of Doomsday.
Also you want to known Why Batman hasn't been green lite. Its not because of script issue and Ben waiting for right Script. It's because WB isn't willing to commit. Their not sure how well Wonder-Women and Justice League will do. Batman v Superman was a big disappointment. Audience hated the film and WB knows it. Then with flop that was Suicide Squad WB is realizing that unless the pull off a win with Wonder-Women and Justice League the rest of the DCMU will be a waste of time and are doomed to fail as no one will waste the time to go see them. They are trying to go different directions but it maybe to late for that. They hired wrong writers and went the wrong route and proved why Marvel is so successful.
I think Justice League will suck and I have no desire to see it. I am looking forward to Wonder-Women but that's about it.