I think you can make a good balance. Some books can be more episodic or self contained, and then you have books that move the storyline forward.
The only danger in escalating conflicts is the lure to 'one up' yourself in each conflict. Luckily I don't see that happening, since Typhon Pact has been more of a cold war than a war like with the borg.
Yeah. I haven't followed them myself, but based on reviews and comment I've seen online, it sounds like the main Star Wars novels focused on Luke, Han, Leia, and their family and allies fell into this after they New Jedi Order series. They appearently just keep piling huge galaxy spanning wars one after the other. I know it is called Star Wars, but before NJO they did to do some smaller conflicts.
Honestly, I think what we are getting now is a lot like what we would get with a new Prime 24th C series. These kinds of big arcs based stories are popular right now, so I have if Trek was on TV right now they'd be doing this kind of thing.