Poldark is a costume drama set after in Cornwall in the late 1700's and early 1800's. The main character Ross Poldark played by (the hottest dwarf in Middle Earth/the least mopey day vampire in recent history) Aiden Turner returns home after the end of the American Revolution, only to find that his father has died, he has inherited more debt than capitol, and his cousin is set to marry the woman he loves. The TV series is based on a book series.
Banished is also a costume drama set in a convict colony of New South Wales Australia. It stars a bunch of actors that I don't know that well and Russel Tovy (The Cowardly Werewolf from Being Human) UK. This drama is supposed to show how harsh the conditions are for the prisoners. While the men have to do back breaking labor(breaking large rocks in to medium size rocks and then moving the medium sized rock, chopping wood and digging)the women do cooking and cleaning(washing clothes), for all the convicts and soldier. The women are also supposed to supple all the soldiers with sex. There is 1 woman to every 5 men and sometimes the women have to share a solider.
I much prefer Poldark to Banished. Poldark is a very streamlined story, there aren't a lot of characters and you do get into their heads. They don't show the characters but more often they will tell you what the think and feel. Ross and Demelza are the worst for this. Over all it's a great show, if you like Jane Austen novels or Catherine Cookson novels you will like Poldark.
Some of conflicts in Banished seem very forced and in order to keep the show going at a good pace. There is little to no introspection from the characters and there are too many character.