Do you think its wise to open Traditional and Roth IRA with vanguard and TDA separetly.
and keep contributions to 60-40 split between traditional and roth
That certainly is a strategy to spread fiduciary risk. (or cybercrime; while you should be covered by insurance / SIPC guarantees if it happens, that doesn't mean you will not be without your money for some time, while they process claims)
One other consideration: one thing I like about TD is the relatively low value to qualify for VIP status, which they call Apex. There are a lot of fees waived when you reach Apex status, e.g. the $20 fee for a corporate buyout. The level is $100k. While the letter of the law is that this is on an account basis, I was hovering around this level with the sum total of a Roth and taxable account, and on my 2nd try to plead my case, they granted it on a total value basis. Whether it's TD or not, you might want to see at what level you rise above the unwashed masses, and if your target is somewhere above that then you might want to keep your "saving power" (like "spending power" in a shopping / bargaining sense) with one company.
Of course, you could also plot to do that sometime in the future, switching one of your accounts to the same broker and gathering up a transfer / referral bonus along the way. But that $100's of dollars or xx free trades is meant to deal with the trading costs of establishing your new account, really.