Easy way to get over concrete undulations is a thin screed of sand then vapour barrier insulation then flooring chipboard stagger the insulation and chipboard joints and pva glue board joints keeping a margine at edges for any expansion. This worked for years on sales offices on housing sites...
The problem I see in your idea of cutting veneers with a bandsaw is saw scratch and speed of cut there is a system,From the USA that clamps to a bandsaw set on rollers with a vernier calliper type adjustment and they even comment that the flow speed is most important, the way to control speed is...