Unless there are French school holidays in the last week of March, midweek I'd expect it to be quiet in the parks. Its not UK school holidays at that time, the 15th anniversary stuff will have finished, and the parks will close midweek at 6 or 7pm. No fireworks at DLRP, unless its high summer season, New Years Eve, or Bonfire night (or very occasionally for a special occasion like St Davids Day etc).