Don't worry, I'm not a fan of large trees.
I've been in this property 23 years and over that time I have totally removed over 15 leylandii circa 30 feet high including root balls and pruned every other tree in the garden to keep them manageable.
Over the last two days I have also pruned trees on both sides of me for my neighbours. Not really out of any altruistic purpose, more just for my benefit to let more light into my garden.
The monkey puzzles are very sharp yes even at that size, certainly wouldn't fancy climbing or pruning a full size one
Thanks for the props re the fence panels.