The cleaning takes way too long and requires so much movement between two places that never change. It's boring and if you leave it you have to look at a disgusting base and you easily lose things on the floor. If it was a couple trash piles away from the main part of the base, that would be okay, and the dirt is fine (except on the roof), but there's a countless amount of trash.
Also, playing on Hard++ does make it faster but when you get faster signal finding through upgrades Normal seems more appropriate. I think there should be a mixture between the two so the upgrades still fix the boredom but the time between things is reduced.