Hi Ruth,
One of my friends works as a commercial property solicitor. Once qualified she went to work in London for a top 100 firm and her local firm paid her the London salary to come back and work for them!
There is always work in both fields, I guess it comes down to your character? Family law can be draining and can trigger previous personal life events for some people.
In my opinion, I’d say there is a ton of work in property law and there is less attachment to the caseload.
Hope this helps.