Might be best to look at the bonuses, and think about what sort of size those bonuses become reasonable. The inability to interact meaningfully with 'man-sized' objects is a big thing, I probably wouldn't apply it to anyone shorter than about eight feet. Same with the bonus to strength, you have to remember that this is an intrinsic bonus that has nothing to do with their muscles.
Really, it's up to you and/or your GM. A lot of the modifiers are subjective.
