Da&xuan, We are taking the Waterfront ballroom too and I was very bothered by the pillars after my colleagues said some guests may be offended that we put them at seats with blocked view.
But my hubby2be said no matter how pillar-free the ballroom is, there are always some guests whose back are facing the stage.
For my case, I think I might arrange the VIP tables somewhere nearer to the blocked-view tables (not up front near the stage) so these guests feel important when the hosts are near them?