As others here have shown, there are a lot more issues involved in this decision than what you can put up on a message board. Your wife has to be completely involved in whatever decision you make in this regard since she will be the one who will have to deal with you being gone 4-5 days/wk all while raising a kid by herself. In that regard, this decision needs to be made between you and your wife.

If you do make the leap, definitely get back instrument proficient (current and proficient are two different things)...especially if there is a sim portion to the interview. I would also make sure to review the systems of the multi that you flew, and possibly even go up for a few hours again with an instructor. You might study the instrument regs and oral guide, too, just to refresh your mind.