As said, set at seat height, which happens to work out so that suspension isn't uncomfortably high up the trees when set a little over tarp width.
On the critter and crawly issue...in the tropics everything climbs! Things can get into the hammock if it isn't fully enclosed and some will manage even then. Ants will want to use the suspension as a short cut between trees. Giant centipedes are quite capable of walking down 3mm lines and taking up residence in folds and pockets left open. Leeches don't crawl so far, but you don't want to be up against vegetation.
My friend had a sun bear stick its head under his tarp one night and give him a good sniff! Possibly more height would have been comforting, but sun bears are great climbers too!
Most important thing, once it is dark, stay in the hammock...and don't drop crumbs on the forest floor or you will create an ant carpet to welcome you in the morning.