You don't need the unit packs, they just add graphics to make the different types of units more detailed (like now turkish troops look more turkish or whatever) – you really only need the expansion DLC, the things that add features you're interested in. Particularly the different starts like Charlemange, Old Gods, and the cool stuff like Way of Life.And to whet your appetite here's one of my recent stories:So I'm playing as Powys in a Charlemagne start, and I've grabbed my de jure territory, holding the counties directly. I look around and find a claimant to a nearby territory to invite to court, then grant him one of the counties and win him the one with his claim. Meanwhile, I've married a genius and had 3 sons, the third of which inherited the genius trait. So I'm considering options that will allow me to play as the third son. Just as the war is ending, my second son takes ill and dies. Now I'd like to expand further, but I can't pull the giveaway-press claim trick unless I revoke a territory first. So I plot to revoke one of the two my new vassal now has, succeed in the plot and the vassal rebels to stop me. I move my armies in to crush him, and get killed in the battle. I win the war, but as my son who is still 9 or 10. So now the genius is my brother and heir, at the age of 5 or so.I've now got 3 counties, plus a vassal in prison who hates me. I invite a claimant to the remaining county from Gwynedd, give him the Gwynedd county I own, and attack and conquer the remaining one. So now I have a powerful vassal that loves me unconditionally and another one that hates me completely, and is running a faction from prison. And my ambitious uncle (who therefore also hates me), has taken over as regent.Unbeknownst to me, my powerful ally in East Anglia has died, so just as I settle in to consolidate and regain strength, my southern neighbor attacks and calls in Mercia. I try a desperate gamble, hiring mercs I can barely afford and bribing my uncle with honorary titles and wards so he'll let me sell off a prisoner. I win a big battle and disband the mercs, but Mercia brings in more troops and destroys me. I find out that my rebellious vassal is leading a plot so I have him arrested with the plan of revoking his county so I can get more troops. He escapes arrest and attacks. So faced with 2 wars and very few troops, I surrender to my neighbor and his allies (losing a de jure county, but it became independent). I gather all my troops and just before the rebellious count is going win a siege, attack a raise the defending levies. I hope to reduce his forces enough to break the siege, but the end result is that losing the battle loses me the war instantly. So game over right? Or at least a long rebuilding process ahead of me. Except it turns out that the war the rebel count waged was to install my brother as king instead of me. Instead of being down to 3 counties, only 1 directly held, and still having to find a way to play as the genius brother, now I am the genius, I have 4 counties and easily take back the 5th, the rebel has a positive opinion of me, and to top it all off, I no longer owe money to the Jews.So... I highly recommend this game.