When I first started, I tried to write something meaningful on every cache, including being honest about the difficulties I had finding the cache so that the person after me might benefit from my struggles. Oh man, did I piss off a bunch of cache creators, including having a DNF deleted and receiving an e-mail that I should stop geocaching.
Those negative responses didn't deter me from continuing with my honesty. Because the thing is, not everyone thinks the same. The first light post cache I found was almost a DNF because I had never seen one before and would not have thought to touch a large utility pole. I ran into more experienced cachers at a park that day and they told me about that type of cache. Most of the other finders thought that was a standard cache, but it was totally new and difficult to me. Everyone playing the game is playing at different levels and coming from different places, so maybe I can give them a hand in my logs, you know? I also used to try to say something really positive if I had a great time at a cache.
What I've noticed is that people delete my photos or delete my logs or get pissed off at my honesty and assume I was attacking their precious cache. What I've also noticed is certain cache creators whose coordinates are consistently 30 feet off, badly written poems, really lame hints, general mocking of anyone who is new to the game, poor terrain ratings, and so on.
Which is to say, do whatever the hell you want. Nobody in this game is actually working to make the game enjoyable for everyone, they're making the game enjoyable for themselves. I photograph something at every cache, because I like photography. Cache creators regularly delete my photographs, because the game is about something else to them and they don't care that it affects my game. I no longer post meaningful logs, because I'm just tired of putting effort into something that I think no one really cares about.
F*ck etiquette. Play your own game. If a lengthy log is annoying, I can scroll past it and a cache creator can easily delete that e-mail. Honestly, your words are not a burden, and don't let anyone treat you like they are.