I say its about a tie with a slight edge going to the goodguys. Doomsday and Lobo are nonfactors here as niether can fly and being only physical fighters, both could be remover from the battle field by the good guys using Thor's hammer or SS tranmutation abilities.
That leaves 4 against Darkseid and Thanos. Now, if Darkseid before he was powered down, him and Thanos would win hands down. But as his Omega beams can now be blocked by heat vision and who knows what else and the other side has the Thor's Godblast and SS/Hal's energy fire power (could SS inhance Hal's ring?) and I think they would edge out Darkseid and Thanos, barely.
If its Thor, SS, MM, and GL (Hal) vs Thanos, Darkseid, Doomsday, Lobo then I don't see the goodguys having much chance. Any combination of 2 of the 4 "bad" guys could give them problems, all 4 I think is a bit much.
If you're throwing in Gladiator, Superman and Champion (I assume without the power gem) then it would level the playing field a lot more and probably give them a big advantage just because of the numbers.
Well, I could be wrong Wally.....but thinking that Doomsday and Lobo are Earth bound does make them easy pickin's for the flyers. It could quickly come down to a 4 on 2. But throwing in the 3 other guys was to combat Golem's statement that Thanos could take on all 4 by himself. If you add the other 3: Champion, Gladiator, and Superman, I see the 7 squashing the 4 bad guys. Just my opinion though. 😉