Mandatory "go and have ideas" time? Also, Mandatory Fun Day? The flexibility to go and cruise round the city would be amazing for me (if I got a job). Tell me that I have to do it, and when, and my reply will be my resignation.
Plus think of this way: how many times do you resolve ideas passively in the shower, out on a walk, picking up dry cleaning/doing laundry, out shopping, etc.?
There's a reason that happens and just like exercise, if you don't schedule it, it's easy to let it slide when things get busy.