Differences Between Terrorized Acts

If I'm already level 93, is there any difference between which Act I decide to terrorize? Besides the obvious of end bosses etc? I personally enjoy running Act 1 but would rather be more efficient if possible! Thanks!

Aside from the choice of end boss, the main differences are in average number of elites (still relevant for heralds for now as well) and in the mob types you encounter.

Avg elites give you an order of 'best acts' as follows:
1) Act 2 with 231
2) Act 1 with 220
3) Act 5 with 183
4) Act 3 with 161
5) Act 4 with 51
(credit for those numbers goes to Pavke)

Realistically, acts 1 and 2 are near equal in that regard and take first place.
Acts 3 and 5 are then again close together but noticeably behind acts 1 and 2.
And we all knew act 4 is way too short to ever win anything.

With regards to mob type, the benefits of each act depend a bit on your class/build.
A2 for example has a fair few magic immunes in the tombs which isn't ideal for say a zerker. Especially if you're talking about T5 heralds.
A1 on the other hand tends to have mobs that are exceptionally easy to kill but Fallen also keep running away after one dies which can be annoying and delaying in its own right.

Personally, I tend to switch it up between A1 and A2, depending on the build I'm on or really just depending on the mood I'm in. They feel a lot more efficient than the others when it comes to full act clears. Though A3, 4 and 5 do make for some nice selective rotational TZs. So ideally, timing permitting, just combine both: run a rotational TZ outside of act1/2 to get a couple heralds prepped (to make it worth it) and then shard a1/2 from there.

Though depending on what really ends up happening with the Herald changes now that they've gotten some PTR feedback, that might all become a lot less relevant.

Act 1, for now at least, is also simply "cheaper" to shard as those shards drop way more often than the others. Though that seems to be changing next patch as well.

I don't know how the drops work exactly, I've been under the assumption that all mobs are equal (i.e. an elite or unique in A1 is the same as in A2).

I don't know how super unique drops.

With that said A1 and A2 shards drop the most and they have the easiest to access elites and seem to have more.

If you're just doing what you can then it makes sense to focus on A1 and A2.

I usually shard act 1 and maybe 2 then do whatever is on rotation then move back to Act 1.

If I intend to shard multiple acts I draw ire in the harder acts and try to spawn heralds in easier areas.