Adding extra words is a nice addition, just one has to be careful with all his steps because
* the chance is millions¹ of times higher somebody steals the seed and extra words than find the same wallet by collision, hence it's important how the wallet was created (safely) and how the wallet and backup are stored
* the chance is millions of times higher the user makes something overly complicated he doesn't understand and he cannot recover his own wallet at a later time.

Notes:
¹ Maybe you go on with reading this topic