Warband 1
Theoden, King of Rohan on armoured horse, heavy armour and shield
2 Sons of Eorl
2 Rohan Royal Guard

Warband 2
Eomer Knight of Pellenor on armoured horse
2 Sons of Eorl
4 Westfold redshields

Warband 3
Erkenbrand, Captain on Rohan on horse
5 Westfold redshields

Warband 4
Eorl the Young
5 Westfold redshields

total: 701

might: 12
models: 24

If you are going for all might it's ok but you are quite low on warriors. Granted they are all mounted but you'd even be outnumbered by elves. You'd have to use that might very efficiently if you want to last.

omg that avatar lol

Yes youre right :)