Battles are expensive. Hell they barely even mention the destroying of Jaime's army at riverun and whispering wood in the first season. Just that they sacrificed some men and captured him. I think they have a big battle scene towards the end of the season from what we've been hearing though.
yes, exactly there is a big battle near the end of this season. It is the biggest and best described battle in the books as well, and it will be in the series and the script of the episode is written by Martin.
And for the other point, yes it is something that you could say of the books as well in general. George Martin provides immense stuff that is preparing for a very big and complex drama/action, which has in most parts still not been delivered. But personally I am very confident, because you see in smallisher story arcs how well that actually happens. Book readers should know what I am referring to (several events). Just be patient and enjoy the fine story arcs, and especially the very well thought-out character developments and reasons for their actions. You will be surprised many times and yet all actions and events seems reasonable for the individual character and realistic in general.
and more battle-scenes in the series would be great, really a shame they have only a couple of million dolllar. Still, it is better they do it this way and everything looks good than more stuff that look crap.
