My 2 cents:
I have all my accounts at Vanguard.
A couple of years back we were given a large sum of money from wife's parents, and I opened a Schwab brokerage account. I loved their interface, their trading tools are miles ahead of Vanguard - playing with them was tempting myself to go into trading, stock-picking, you name any deviation from DCA and lazy passive investing.
What made me NOT move the funds into Schwab was the weekly phone calls from an advisor, daily emails even though I thought I had turned off all notifications, etc., and a constant up-selling of advisory products.
It made me reflect that as a barely qualified Vanguard Flagship client, I've received zero phone calls to try/buy advisory products. I've had Vanguard since 2010 via a 401k, and at the most I've received a couple of postcards/emails a year to try their advisory service.
For this reason alone, and to continue DCA into index funds, I decided not to use Schwab.
Your situation is different, but Chuck is a salesman, he loves to sell you a good deal.
Now, if I was into trading with ETFs, I'd definitely use Schwab or TD or Interactive Brokers instead of Vanguard.