Do you really think that whining about your wife and your family plans isn't begging? Please sir... can I have more?
Ask for what you deserve or go and get it elsewhere.
Asking for more because you are about to have a family is begging, it comes across as asking for a favour. Your boss, or his boss, or the boss you don't like may grant you the pay rise but you're positioning it as a market average pay rise at best or a favour which you owe gratitude for at worse.
If you are worth more, tell me why and ask for it like an adult; don't bullshit me, I know your worth and so do you; if we disagree on that point, prove me wrong or get another job in this incredibly liquid market.
IT guys are fucking terrible at negotiating. This letter and your response to me are classic examples.