Christian McArdle wrote:
Look at the overflow, too! I'm sure you can improve this!

Yes, my new toilet cistern comes with a syphonless flap valve. Looks much
simpler and requires no ugly overflow pipe (it goes straight down the bowl).

The "internal overflow" is available on cisterns with
siphons as well as any other sort. The flap valve is
a crap idea that should be consigned to the dustbin.