After doing some profiling I found that one of the current bottleneck in sculpt mode for supporting the new tools is in pbvh_update_draw_buffers when a large number of nodes is tagged to update and redraw each frame. This affects performance when working with big brushes on high poly meshes as well as some of the new sculpt mode tools.
There are some new tools in sculpt mode that needs to update/redraw all PBVH nodes in real-time, such as the mesh and mask filters, transform tools or pose tools. To make these tools faster from sculpting mode, the current approach is to delay a viewport update as much as possible, processing multiple iterations at once.
For these tools, it would be nice to have a way to update and redraw the whole mesh at once in the fastest way possible, skipping all PBVH updates and rebuild operations until the tool finishes.