Generally no. Mom has a pretty solid support system in place there; nothing in the law states that Mom needs to work live outside of her parents house to be a decent parent. If anything it may - in some instances - be a point in her favor.
While of course we cannot know for sure, I will go out on a limb and disagree with what Lawrence has said; MANY of us here have vast experience with custody matters in local family courts and generally speaking we - as a collective - have a pretty good record of "getting it right", if you will. I for one would rather you didn't waste your money and time trying to change custody if you don't have a valid reason for doing so.
Mom's financial and home situation are more than adequate by all accounts; if you wish to have custody changed at this point you'll need to either prove Mom unfit (and nothing you have said here comes close to that), or show that there has been a significant change of circumstances in the child's life.
For example:
Mom is in jail, or is in hospital and expected to remain so for awhile.
There is abuse and/or neglect.
Mom has moved in a level 3 convicted sex offender.
See where I'm going here?
I'm...not entirely sure why you think any opinions have been biased.
And...honestly? The court will not be too sympathetic to you choosing to have extra children while attempting to reduce or not being able to afford to support the first. Remember your wife's infidelity is not the fault of your child.