World Edit is a very powerful and convenient tool for building, and now every player can use it on their claimed plots (only) in /boxland. Please note, even if you can select a larger selection, any action you initiate will take place in your current plot (where you are) and when they hit a plot boundary it will stop. Merged plots are treated as one plot, so you can WE the whole thing. If you are already familiar with WorldEdit, grab a wooden axe and you are good to go. If not, well... it's going to take a little studying to get up to speed. Here's a video that may help introduce you to it (and Grian is a good channel for building tips in general): Or just ask other players online that are already familiar.