"Take it all" is a phrase that signifies a sense of completeness and entirety, but sometimes you may need a variation of this phrase to express the same meaning. Some of the synonyms you can use include "take everything," "take the whole thing," "take all of it," "take the full load," "take the entirety," and "take the whole package." Each of these expressions is proper and will hinge on the context of your message. However, some of these phrases may be more appropriate in certain situations, such as "take everything" or "take all of it," which implies a sense of urgency or importance. In summary, a good writer knows how to vary his vocabulary to express the same idea differently.