This build doesn't struggle with various trash mobs (it does have low-medium single target at best though) and it is more of a mindset thing than anything else to clear bigger packs. Amazing grace procs very often with 5fpa and with smaxed sanguine covenant you ensure that you are healing for at least 4k/sec while fighting stuff. One thing though is that sometimes you get the visual effect from blood thorns but you technically aren't in range so you aren't "leeching" (this might be a realm feature) but it happens often enough to be mentioned, I recommend divine apparition directly on the feet of whatever dudes you are fighting when this happens.
You can always throw some more filler points in rapture if you aren't hitting your breakpoints and smaxed blood thorns will eventually get annoying to play with if you ever do stuff like dimensional lab or any boss for that matter because your blood thorns cost will outpace your mana on attack hard. Gear a a5 merc with basic stuff and teleport with him + hoplites.
The spec is easily in a better spot than holy melee atm (much tankier in raw EHP and 200k less defense feels more tanky due to 5fpa/avoid).