More importantly, it's hard to make a truly broken list for Fantasy. The game is very player decision-centric-- list building is maybe 10% of the game. If your opponent is stupid, or you're just slightly better at the game overall, you'll come out on top regardless of what army you're playing. I've seen goblins beat daemons of Tzeentch (complete with Kairos Fateweaver and the Blue Scribes) purely because the goblin player was a better player.
Asking for a broken list won't help you win games. It might give you an edge if your opponents are equally incompetent, but when your reaction is "I need a broken army to play this game," that's probably not the case.
I would play 2000 points instead of 3000-- it's a more easily handled game size, and it's one that I think is more conductive to getting better at the game. 7th was balanced specifically at 2000 points, and 8th probably is too, although 2500 points seems reasonable in 8th as well.
What you're really after is playing at a points level where emphasis is on your Core units and how you're using them. Vary what you do from game to game, and figure out what works and what doesn't. Lizardmen are a strong army-- you'll figure out how to win with them sooner, rather than later, I think.
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