simple pictures :

some suggestions of things what impres me:

first of all try to avoid using cuboids

second i like te secret things basements that are hard to find

i like things like tiny from outside and big from inside the cinema and the white tower from city are examples

i really give bonus points for originality(things i never saw in minecraft)

i apreciate big places with high roofs sometime i'm claustrofobic when i enter some tiny structures ....

just try to avoid making structures like this:

they are very annoyng

maybe already know this so you can and make it