Index stock funds or individual stocks in taxable, bonds and REITs in tax-advantaged. Avoid combo or active managed funds if you can help it, stick to indexes to eliminate cap gains. I get hit with CGs every year from old Fido funds that I’ve held for 30 years, but am keeping income low for ACA purposes so don’t sell them off.
Bond yield in most cases does not have tax bennies, CGs and divs do (you basically get ~$80k tax-free every year for MFJ filing).
And maybe it’s time to go from three to two brokerage vendors … before Vanguard starts absorbing the fees/fines. Besides, after threatening for 4 or 5 years, it looks like Vanguard is going to start charging fees for paper statements if you have less than 1MM in their coffers -ex 401k. Neither Schwab, nor Fidelity charge, so I’m splitting my Vanguard funds between the two. I would prefer more diversification, but if Vanguard thinks I’m not worth a stamp and the printing costs, far be it from me to argue.