I think your right for the rulling on that card but I'm not to sure. You can check the rule book and wizards forums just to be sure.
I might take out a few creatures and add some more protect or spell interaction.
Your goal is to flood the field and kill him with creatures quickly. I think you can drop Legion Loyalist and maybe a few Bomber Corps and Firefist Striker . Maybe drop one of each of those cards and a few more supporting instants, sorcery and enchantments.
I'm helping a friend build a battalion deck as well and put around 20 creatures to trigger battalion. More Frontline Medic would be nice and Firemane Avenger. Add Tajic, Blade of the Legion for sure he is deff good for battalion. Boros Charm I'd add or atleast side board. Skyknight Legionnaire I think you can side board another 2 if you encounter more flying or no flyers to break him down super quick cause he can't block them. Arrows of Justice be good to side board if not add a few to ping and kill a guy that threatens your battalion. Oblivion Ring would be nice to have a couple incase you need to get through a big guy or just stop them from attacking with them. Think about Gleam of Battle , Wojek Halberdiers and Angelic Skirmisher as well.
I looked around and those seem to be nice to consider as well. These cards might help if not better refine your deck.