I like locks, though I have to say I'm not a glutton for hard work so don't like doing too many per day! It is nice to have the occasional lock free run as well.
I still haven't mustered up the courage to steer yet, so, by default, I'm on locking duties (and how many times have I heard "oh, he lets you do all the hard work then"!) I enjoy the excercise - it's great for getting rid of a few excess pounds. I also enjoy the social side of it - I've met some really interesting people and had great conversations while pairing up with another boat. Saying that I've met a few people I'd be happy not to come across again. Dave's had similar experiences at the tiller sharing locks - sometimes he and the other steerer are so deep in animated conversation that they don't notice the gates are open, other times you can see him willing the water to rise as he's given up trying to make conversation.
I absolutely love it when we pair up with another boat and the lock operators get a good system going between you and suddenly you're saying "oh - we're at top lock already" - it's a great feeling. Equally frustrating when you pair up with people who don't pull their weight or faff around and you end up doing twice the work instead of halving it.
I definitely think points should be awarded to locks - narrow locks are way easier than broad locks, and I'd rate the broad locks on the L&L higher than those on the GU because there's no footway over the bottom gates, meaning you have to do a lot of walking if you open both sets of paddles. I gave up about half way up the Wigan Flight and decided we were going to have a leisurely journey with paddles only opened on one side (that was before we ran out of water - but that's another story!)
That's just my experiences so far - still fairly new to this