It's not like banning a troll for this would be any harder than '//set'ing the spawn with dirt.' If an administrator is doing their job (i.e. monitoring the spawn while watching each player's commands), this shouldn't be a problem.
Wouldn't it crash the server if Fluid Spread got enabled and someone pasted a massive hsphere of water?
No. Any lag experienced from a large amount of flowing water would be incredibly piecemeal; a basic redstone function would have a higher probability of lagging the server, as Minecraft fluids only spread to a certain point [that point being their range].
I run a server (shadow.ga) with enabled-fluidspread and nothing of the sort has affected in-game processes (or response time).
You could actually do more damage with `//set` gravel, sand, etc - as blocks with gravity properties would have a higher range to travel (i.e, if pasted at the tallest point within a world, 256); and not to mention, these materials update at a faster pace than spreading fluids.
Block OP's permission to use water/lava with W/E and allow the buckets permanently, why? Constantly used to just grief and crash the server, please do this. Remember //cyl //sphere etc. Because if they are allowed it is still possible to crash the server, please remove the permission.
Cannot confirm on my test server. The water starts flowing as soon as it appears.
Async? TF and s.ga both use AWE.
[Also not using TF-WorldEdit, and nor is TotalFreedom.]
I guess AsyncWorldEdit prevents edits from doing block updates, then. I can't think of any other objections for now, but if Mojang keeps the 1.13 water physics as they are in the snapshots, we'll have to turn it back off when we update because of this: redd.it/8344fh.
Ut administrator sim, non me facit deum. Homo sum, ergo etiam possum errare.