I would like to share some images of where I spend most of my time. I have a 2x cave spider grinder with a crusher which allows for a one hit kill (although I usually use potions). Right behind the grinder is a 3x slime chuck farm. I added water channels around it so the slime are funneled into a killing area which is still within the cave spider spawner activation zone. This is a very effective area for xp and slime balls. I can usually hit lvl 30 within 20 minutes with a stack/stack and a half of slime balls. When not using the spawners, I added redstone lamps to deactivate them. The brick area is right below sea level and where I store most of my items. I connected both areas with two shafts, one with ladders for going up and one with a free fall into an 8 block water stop (not sure what to call it). I also have a small farm approximately 15 blocks below the upper res. You should be able to find images here: http://imgur.com/a/k0BLe#3
Thank you. I opened up one of the cave spider rooms and uncovered one of the tunnels which leads to the crusher. I added very little of my own design, credit goes to the xisumavoid and sokar. Both spawners share the same y coord. Here are a couple of images: http://imgur.com/a/zkdGe#3
Very nice! I've got a similar base... I think I'm going to add some water channels to my slime farm as well. Of course, I've got 35.6 personal projects going on at the moment!
The water channels made a HUGE difference in the amount of slime I was able to spawn. I tried to set the lava "blade" lower to take care of the large AND medium sized slime, but I lost too many of the small slime in the process. I also tried running the large slime into cactus, which worked for them, but again I started to loose too many of the small ones. I had to add a water channel above the lava because when the big boys would hit it, my wool floor would catch on fire.