Thundering Host might not be a bad addition, since it can be a flexible pump and/or healing with all the plains sites you plan on running with. I'd recommend tossing in a couple copies, perhaps replacing a
Simbelmyne and a
Rohirrim Javelin or two.
With Strength To Fight is a less desirable healing option, and probably not necessary with the
Rohirrim Shields (which would have been my first choice), but hey...it IS an option if you're just not getting enough healing otherwise. Using
Firefoot, Eomer's Steed instead of the version you have would give you a LITTLE more condition removal (and is cheaper, which is always nice for the expensive Rohirrim).
Not sure if you can fit them in, but a copy or two of
Rohirrim Helm might be nice for canceling skirmishes with any BIG minions that survive archery. Chances are pretty good they won't be able to exert to cancel. *shrug* Just a thought.
Eomer's Spear, Trusty Weapon would be a very nice addition for finishing minions off...either with the
damage bonus (should he win) or with the option to discard for a free wound...and possibly pull back with Merry and use again that same skirmish! Lethal. 8)
Also consider:
Dispatched With Haste - gives you possession removal if you need it but more importantly gives all your mounted guys a nice boost
Rohirrim Diadem - can turn extra possessions into a strength boost if you desperately need it
Cast From The Hall - not very useful if you don't pull it early enough, but considering you have at least 16 possessions you'll be playing from hand at SOME point, it certainly can't hurt to toss a copy in, right?
Precise Attack - could add a little extra and/or targetted archery if you can somehow squeeze a couple in
Rohirrim Doorwarden - kind of costly, but with certain companions possibly bearing three (or more!) possessions, having one of these guys around certainly couldn't hurt!
Just a few suggestions. I would most strongly recommend
Eomer's Spear, Trusty Weapon (almost a must in this deck) and
Thundering Host, which would solve a couple small weaknesses at once.
LOVE the deck, though. I have a very similiar one that revolves around
Eowyn, Restless Maiden and
Dernhelm's Blade. THAT is one lethal combo there.