The nature of the story is part of the problem. BOB was, as much as any TV work, an actual story. There really was an E-Company who fought in all of those battles and which actually ended up in Berchtesgarten.
Now they were thus tied to this formula when doing this Pacific. The problem is that here we are looking at a much more complex battle order. They found a group that had several interesting battles, but there is no one company or unit that participated in a series of battles that the lay historian will have heard of in the way that happened in Europe. The war was also more difficult to cover because it featured Naval and air battles dis-similar from the story in Europe.
And the casulty rates were such that, to be realistic, such a company would have to be all killed off by the end of the series.
And, of course, the basic story of the Pacific is very different from that of Europe. The military, while the won the war, did not end up fighting its way into the enemy's home due to the A-Bomb.
To that end, a little fiction might have been in order here. A fictional group of Marines who show up at all of the major battles, and happen to be on board in the varrious Navy incidents, with brothers or childhood friends in the Air Corps, might have been more entertaining.