Here is what I"m doing but it takes multiple processes..
right up until about 1/2 mm before the top surface, I print with a very low infill (like 2% or whatever) without random infill.
Then next process I switch to about 30% and print several layers, I make sure to chagne the infill direction 90 degrees so that there is something to print on.
Then when the top surface prints it can have a nice surface.
Problems arise when the part isn't nice and evenly flat. This specific part is quite squarish so it can work.
But if I have a part with other pieces sticking out at various points in the print I have to be more creative. A while back ago I had a part with I think 12 processes, each simply adjusting the infill angles and density. Hopefully sometime soon the software will do that automatically. To date it's still worth the time to do the processes rather than print the whole model at a higher infill. The pictured print is a 21 hour print approx... would be around 70 hours with a higher infill I think.... that and all that wasted plastic.