If it were me I would remove those levelers like you mentioned, and I'd also add the 2x's and ply bottom, and I'd line it w/ pond liner or even linoleum just to keep spills off floor.
I'd use shims to level the tank underneath the new wood bottom.
Make sure to keep some extra laminant flooring stashed in case they stop making it and you need to repair down the road when selling the house or whatever.
There's a fine line between owning your tank, and having your tank own you!_________________________________________
120G SCA starfire, tunze 1073.02 return pump, Geisemann reflexx 4xT5, 2x panorama pro LED strips, 2x Vortech MP 20's, 40g sump w/ fuge.