I would not move that wall out. You have the window in the bedroom that you're messing with by moving the wall.
Also, by moving the tub, you may also have to move the plumbing (drain). Do you have the cost of (possibly) moving plumbing around in your budget?
Finally, I tell home owners that are considering major remodeling projects to also get the advice of a local realtor. If a realtor says it would be beneficial, that's a big thumbs up however, if they tell you it's not going to give you any return on investment OR actually hurt the homes value, well then you have your answer.