We are currently trialing an addon which makes topics "auto update" without you needing to refresh. This works by refreshing only the minimum information required, rather than refreshing the entire thread. That should help to reduce some of the load caused by larger discussion and game threads which can often receive many posts in quick succession.
Let us know how it's working for you, so we can continue tweaking it. I've trialed it in the past on the test forum, but this is really something that we need live testing for to see if it'll be suitable for us.