OK, I can't tell if the 129 is pre or post tax. What percent of your take home income goes to housing? The rule I like is the one Warren uses, with 50% going to fixed or recurring expenses (this includes mortgage, utlitilites, phone, basic groceries), 20% to spending and 20% to saving.
See if changing from a 15 to 30 really even saves you much, after taking in the closing costs and having to pay more in interest.
Also and maybe I'm the minority here, I see a house is primarily a place to live in, not as an investment. So why did you buy this big beautiful home, and already you are thinking of renting it out? Just buy the house that you would be happy to live in, that is within your income, and invest the rest of the money. Or if you want to buy investment property, treat that separately, otherwise you may buy more house than you need, fooling yourself it is some kind of investment.