Where do I start?
Bev makers, specifically the drainage points beneath them which get clogged with minute particles. Sinks, every a/c type just about but the 767 and the Airbus fleets particularly useless. Dedicated airvent in Airbus galleys which shoots out tiny hail stones when you are least expecting them. Double cannister stowages above head height which are a manual handling nightmare. Finally, my least favourite, static waste bins which cannot be accessed for emptying without opening the aircraft door!