[SceptileMaster]

This is going to sound cruel but it's what it means. An Anime cut-out means that the characters basically sound like they are just generic Anime Clichés.

‘Fleshing something out’ generally means giving things adequate room. Don't try and stick lots of situations in a single paragraph, also to structure things nicely. I'm not sure it's word count that matters too much though. I did an short piece in 800 words and managed to fit quite a lot in without what I would consider to be an akward pace (alhough I'm not great, other people could think otherwise). Structure is the key and filler is never a good idea to try and achieve this either.