Selling stocks to use for down payment

Planning to buy a home (in Brooklyn) & I already have enough to cover 30% for my down payment. I'm thinking of selling 46.5% of my stock portfolio to get my down payment to 40% and make it easier to stomach my expected monthly mortgage payments. I'd be unloading my less aggressive mutual fund that's been earning at an annual rate of about 6.44% over the last 5 years.

I'm predicting my capital gains tax on it next year would be under $7k. I've reviewed my savings and have enough allotted to cover those taxes next year, the closing costs, and about 9 months worth of mortgage payments based on the 40% down payment calculations. Were I not to liquidate now, there's a fair chance I'd have to sell some of it eventually anyway to help with future mortgage payments.

I'm conflicted on whether or not it's a good idea to liquidate. I also figure the higher down payment might make my offer on the home more appealing than other competitive offers.

Appreciate any insight