Which faction provides the biggest test?

[ReluctantSamurai]

Started Armenian campaign on M/M, did not get too far before I decided that my "don't start a war" plan was wrong, restarted and went after Pontus.

Hopefully, you read my Guide to Armenia? It pretty much covers everything you need to know, and how to start out with them.

Am allied with Egypt

About as reliable an ally as the Greeks. Oh wait...they ARE Greeks

Seleucia attacked my three general/four horse archer army with two full stacks of Militia Hoplites.

Wow...it's rare for Seleucia to be the aggressor. Usually it's me going after them.

I owned them

We'll make a horsemen out of you yet

While I had been fighting Egypt and Scythia, rebels had popped up all over the place (not helpful when you're struggling for cash) and I had no spare units to deal with them.

Another reason for staying the heck away from Scythian regions...too many brigands. Scythia, Britannia, and Germania seem to get more than their share of them...only in the vastness of the steppes it takes forever to get to them.

still not seen a merc hoplite including as rebels

You won't see them in rebel stacks much, but in the six regions I posted above, you can recruit them as mercs.....

No Parthians nosing around?

They nose around alot, but in my games, when the AI takes a look at what's sitting inside Artaxarta...they go away without attacking. I did have them lay siege to Artaxarta once, mainly because the their army had one of their two starting cataphracts in it. Vanilla archers don't do a heck of alot of damage to Cats, but each attempt by me to break their siege cost the AI 10-12 horsemen. On the third attempt, I sallied the entire garrison, overwhelmed what was left of their Cat unit, and drove the rest off. They didn't come back again...'course it didn't hurt to have a small cat-army stationed at the border