I'm in the same boat with an older Firefox -- JavaScript is either on or off.

I generally keep it off while browsing for information.

When I'm doing local dev or working with trustworthy sites only, I turn it on.

After a while, the process of toggling it is almost automatic, though it still takes a few clicks and typing.

As I mentioned earlier, I've grown to avoid sites which tell me JS is required, and have found that it's mostly a good thing, because that type of design usually correlates with poor quality content, so they're really doing me a huge favor by denying me.