Level 12 walls ... Suggestion

I have a suggestion for the supercell To Make a Level 12 Walls ...

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Level 12 Walls : Troops ( any ) Move Slower When They Are On Top Of Walls Or Walls Place ( Broken Walls ) ...
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By adding this walls , ppl whom upgrading walls know why they are doing that , as now the walls are not that much effective , many ppl say oh wuts the difference between 10 & 11 !? they all break with 3 maxed out wallbrakers or jumps will skip them easily or Earthquake spell ...

And what do you suggest with regard to the upgrading cost?
with LVL 11 being 4mil a pop, 5 mil would be the cheapest next step.
and 275 x 5mil = 1.375.000.000 ressies ....

where would you like us to find the loot to do these walls? man im still on legos, my head hurts when i even think about lavas lol