Yes ill post my test_land when i get home from lunch in a little bit with my configs for it, i play on the industrial rage server.
I can get more than 1820 by removing ice blocks, how ever this is the only layout that gave me 1820 @ 4.33 eff and had a cool down of 4 seconds and could run more than 1 cycle or didn't require advanced redstone timeing.
Also on the note of using a mob, you can put a inline item detector and wire that to a timer and toggle switch so that when the item detector sees a snowball go though it resets the timer, if the timer goes for more than say 30 seconds then it should kill the system, how ever you would also have to add a item detector to the ice delivery system to ensure ice is still going though.
I have a 0 chamber SUC design with the singularity compressor being powered by the generator its feeding. if you look in this video you can see my 0 chamber suc is running in the back ground on the left.
Ignore the cooldown... The cooldown is there because the last reactor tick doesn't zero the reactor heat. When you start it again it will maintain the same heat levels as before.