There's the clue leading to your solution. Undeveloped 9s who are low grade, can't play with the big boys, drop to those low trophy areas and push around the little guys. No skill, no strategy...(usually later bragging how good they are). Think of HS freshman bullying elementary kids stealing their lunch money)
A skilled TH9 player will waste most of the current 9s (not difficult given the number who gemmed their way without learning ) and an 8 hasn't a chance augainst skilled 9s. That being said, a TH8 is fortunate the average TH9 player has the skill level of a cross eyed aardvark.
Subtlety, deception, and play on greed. Don't overestimate their intelligence.
First of all, most of those types of 9s stay out of the higher trophy leagues. I play in Crystal III between 1950 and 2100 trophies. Elixir is difficult at that level, but DE and gold is plentiful. I can log out and safely assume an hour at least of not being bothered. (Skilled 9s go for the much larger loot and challenge of the higher 9s and 10s).
My base is my own design, doesn't appear unusual etc. No funnels or any obvious play on the AI tendencies. What it does is appear to have obvious strong areas and weak points. I rely on stupidity as my main defense. They'll drop level 6 giants etc expecting to barge right in...and actually be dropping and headed right where I want. Overlapping kill zones of various weapons.
Storages are great deception tools. Research your third storage to a level 3 or 4. At the point it looks big and overflowing, but holds 250-500,000 max. That's a "bright shiny object" theyll go for thinking " easy loot". ( again note, you are deciding where the attack is coming from, not the attacker.) Another nice trick is on main attack routes, place one of your builds there. Giants will stop to wreck it...leaving your weapons time to wreck the giants before they reach the walls. Place a trap right after it...Giants mass to wreck thes build, then run as a group into the spring trap. Bring your Teslas to level 6 as soon as you can. Dedicate a builder to them. At TH8, level 6 Teslas do serious damage.
Subtlety, deception, rely on the usual 9 to be unskilled and an idiot. A skilled 9? You're toast.
I love the mentality of the guy I who's post I pasted above. He'd maybe....with luck, one star the base with 50-60%. Probably one storage of each.

