If the trees were dying due to something that could spread, the tip has to be the best place for them.
Failing that, I stuck a mass of conifer bits around a hedge bottom last year and it's going down very well indeed. Didn't look good in summer, but we didn't mind as it's out of sight anyway - though you may mind browning bits all over the place!

Composting sounds good. I've often wondered if the pH of compost would alter much with the type of tree added (we clip conifers for people and I don't really know what it would do to my pH) so some follow-up from you would help me out ..... please!