For one thing, HTTPSB doesn't hide DOM elements (I consider this out of its primary purpose), so if you still want this feature, you will have to keep ABP (or whatever equivalent does element hiding).

As for Ghostery or Disconnect, they still can be useful if you use HTTPSB in a permissive way (allow-all/block-exceptionally).

You could even use HTTPSB to block nothing at all, but as a mere reporting tool (with very low footprint), to find out what the other blockers did not block, as net requests will still be reported in the matrix.