I'm fanatical about sweeping down the slides before retracting them. On my previous camper, I carried a 7 foot step ladder that was high enough to reach the tops of the slides. But it was always a challenge at different campgrounds and campsites to get the ladder steady enough to comfortably climb up to reach the top. I used a long retractable painters wand with the soft RV brush on the end and simply slid it back and forth over the slides to remove all the debries. However, I never did like the feel of the ladder.
Fast forward, our current 5er has a ladder attached and has 4 slides. Now, is no challenge at all to climb on top of the trailer and sweep down the slides. I quit carrying the 7 foot step ladder as I don't need it any more. The attached ladder is so much more safe, and I don't mind getting on top of the trailer at all any more. Besides, every time I go up, I give the roof a quick inspection and check things out. It's just become a habit now.
There's no easy way to clean them off.
About slide toppers. I'm in the neighborhood also, I don't want slide toppers. We use the camper at home all the time and slides are out. We live in the country with fields on both sides of the house. There is nothing to break the wind, and were we live, the wind is very strong 50% of the time. Very seldom can we put the awning out at home, the wind would rip it off. Slide toppers would flop around too much, and probably end up ripping off too. I'd rather deal with climbing on the roof.