I'm a regular user of Advanced Search. I find it frustrating in the New Experience because it is no longer a persistent screen of its own. It's now more of a popup on top of other screens, and the problem is that it disappears on you when you do something like editing a view. e.g. I spend quite a while setting up a complex set of filters to find the data I'm interested in, and then I realise that I need to add a field to the view. I do that, click Save and then BAM! The search results disappear and I'm back at the screen underneath it. Now I have to click on Advanced Search again, and put in all the filters again to find the results I was looking at.
If this strikes a chord for you, please vote for this at:
https://one.workfront.com/s/idea/0874X000000oNqyQAE/detail
Thank you.