While having professional liability insurance would never be a bad thing, it doesn't seem like it's a necessity in your case, especially if you're not working frequently due to your child (congratulations, by the way!). It would certainly be an asset, however it would increase your cost and likely necessitate a rate increase on your end.
What you may think about doing is getting a quote or two on a short-term policy that you could consider "show-specific". Say, a 12-16 week duration, at a specific venue (or venues), at a relatively low level of coverage - something like $25,000 per occurence / $50,000 aggregate, or 50/100 depending on the size venue, type of equipment, what your specific role is (all things that could have an impact on your financial liability in the event of an accident). If you have a quote handy and know your cost, you'd be able to pull the trigger quickly should a future employer ask you to obtain coverage. More importantly, you'd be prepared for negotations. You'd know immediately the costs associated with obtaining the coverage and would be able to adjust your rates with agility and accuracy, as opposed to shooting in the dark.
