Productivity is the name of the game, right? The combo in a nice rig but what are ya going to do during down time for maintenance? If you go with the bucket truck and the dump box truck, I think you would be ahead of the game. As far a chipper goes, why don't you rent or lease one as needed. This way you company can write off the chipper as biz expense.
During the winter you could put a plow on the dump truck & salt in the box and pick up some extra money with private contracts removing snow. Might even make enough to buy your own chipper for next
spring.
Down the road think about a bob-cat or a front end loader & trailer to expand your biz...just a thought. HC