Some more thoughts:
As long as you can manipulate path this way - it is fine, you can do it in BP. For example, in selenium, this is just one xpath away: '//label[text()=""First Name""]/../input', in UIPath it is also possible to find right field with one selector.
When path becomes more unpredictable, you will have hard times finding your elements in BP, however I can think of a few more tricks.
If you compare it with UIPath (rpachallenge was originally created for their challenge), they have about the same speed by default, however UIPath has an option to remove sendkeys delay (nice to have, but might lead to problems in some cases).
It is also possible to complete it in like 2 seconds executing JS directly, but it is more like cheating.