I would be more concerned with the intersection of "massively planned plot" and "ranger playing really not seeming to care about anything" than I would about the tactical issues. He seems to be having a good time blowing up bad guys and that's about it; it's possible your players aren't really on board with your plan of massive campaign arcs.
That's not a deal-breaker, but it's something worth having a group conversation (totally OOC) about.
One thing I always try to keep in mind when I'm off on a tear, creating lots of cool content, is that I'm primarily doing it for my own enjoyment. If the players see the content and get to enjoy it, fantastic, but my rule of thumb is I ever feel like I'm doing it just for them, then I try to scale back a little bit in terms of how much effort I put into it.
Good luck with the campaign!
This campaign came about because we were fed up with pre-produced campaign arcs, I got the players to come up with backstories all ending in the town of Fallcrest- they all did this, I used this as a jumping off point for the campaign, although I had a good idea where I wanted them to get to in the end. We discussed this as a group before the campaign started.
I'm enjoying the writing, and am sold on 4e when used with MapTools, so I'm having fun, the frustration comes because a character chooses to go his own direction, sometimes against the other players, which I can handle to a degree but the players are getting frustrated at times.
When we get to roleplaying time the Ranger is often uncivil with the NPCs that the other players are trying to befriend, or extract information from, or sympathise with and soon after offer their services to make good whatever terrible thing has occurred. He doesn't do it all the time, and when he does he's funny with it, but sometimes I have to (as the NPC) ignore it because the thread of the narrative will break, even though the other four players are trying to keep hold of it.