Filing a text trade mark gives you wider and stronger rights than registering a logo, where your rights are in the combined words and graphical elements. With a logo, potentially someone else can register the same words but with a different design. If you have a word mark no one else can use those words, with or without a design, so wherever we can we try to register a text trade mark.
If you want to register both the words and separately the logo version, this is treated by all the registries as two applications, so two sets of their fees must be paid. As standard we charge two sets of our advice fees, although we can sometimes be flexible.