So I've come up with two possible lists but I can't choose between them. What are everyone's thoughts?

Isengard
Warband 1
Mauhur

6x Feral Uruks
4x Uruk Pikemen
2x Uruk Crossbowmen

Warband 2
Uruk Shaman w/ Armour

6x Feral Uruks
3x Uruk Pikemen
3x Uruk Crossbowmen

Warband 3
Vrasku (Leader)60

5x Uruk Crossbowmen

499pts. 6 might. 32 units.

Maxing out the crossbows, lots-o-strength 4, getting lots of two attack ferals in. Could be quite effective.

But......

Mordor
Warband 1
Shagrat. Captain of Cirith Ungol w/ Shield

6x Mordor Uruks w/ Shields
6x Mordor Uruks w/ Two-Handed Weapon

Warband 2
The Witch King w/ +3 Might, +4 Will, +2 Fate

6x Morannon Orcs w/ Shields
5x Morannon Orcs w/ Shields, Spears
1x Morannon Orc w/ Shield, Spear, Banner

Warband 3
Shelob

500pts. 6 might. 27 units.

Nasty things in there. Magic, big ol' spider, lots-o-strength 4 and a banner, but it lacks the ranged threat that the Isengard list has. Also, alternatively I could switch out Shagrat for a Black Guard captain for that defence 7 and the boosted courage for having a Nazgul in the army.

Oh, just quickly came up with this smallish, elite Isengard list. Probably putting all my eggs into one basket with this list but let me also know your thoughts on it too.

Isengard
Warband 1
Thrydan Wolfsbane w/ Horse

11x Feral Uruks
1x Uruk Berserker

Warband 2
Saruman w/ Horse (Leader)

6x Uruk Crossbowmen
1x Feral Uruk

500pts. 6 might. 21 units.

Idea being that with the amazing casting abilities of Saruman, he could really disrupt things for my opponent. A nice little immobilize and Thrydan can go headhunt their heroes. I'd have to play it VERY smart though.

Anyway, I look forward to any feedback you guys can give me.

Hard to tell. The first two are two really good armies, in my opinion. The third one could face big troubles in case of harad/grey company/elves. Three Rounds of massive shooting may break them, but is not bad either.
I'd go with your mordor list, but I'd drop shelob to give the WK a Fell Beast.