I honestly have all my add-ons jammed into V20 and only use the retail Blockland to play online with others. (I use port's V20, minus the BLB doors so I can use JVS doors.)
Does anyone do the same? I find it highly convenient with the terrain, actually having my own personal Slopes edit so I can make a chaotic world. (Changed the terrain square size from 16 to 2 and moved the spawn so it was on the ground, not in midair.)