I think there is also a big difference between two types of tax-advantaged accounts, tIRA and Roth IRA.
I'm putting extra stocks in the Roth, where growth can be realized without LTCG's. I put extra bonds in the tIRA, where slow growth reduces the taxes I pay when I withdraw or convert. All while maintaining my AA for the overall portfolio. I still like to maintain 15% bonds in the Roth to allow some over-balancing in bear markets, and the tIRA ends up with something like 50% bonds. My taxable is 100% stocks, mainly because I'm trying to avoid taking large LTCG's while Roth converting and that's what is left. We have about a year's expenses in cash that I don't count as part of the AA, and 2% cash in the taxable account that is part of the AA just for a little liquidity.
For my DM, who's 90 and thinking more of inheritances than herself, I'm doing something similar, but her taxable account takes the place of a Roth account. Again, about 15% bonds in taxable, the rest in stocks that I try not to sell, with the rest of the bonds in a bond-heavy tIRA. No taxes on the stocks when inherited with a stepped up basis, so it's a little like a Roth when used like that.
I've really liked having at least the 15% bond allocation, which I set to 0% when the market dropped to 30% down. So I'm not sure I'd put all my bonds in any one type of account. The same goes for foreign stocks. I actually have all DM's international stock in her taxable account to take advantage of the foreign tax credit. But now I can't rebalance by selling international shares without generating LTCG taxes that would otherwise be avoided by a stepped up basis. So I'd like about 15% international in tIRA/Roth just for that case.
While I can see the appeal of bonds in taxable for short-term spending, I don't think stocks are a good fit with a tIRA. The sooner stocks and their growth can be placed in a Roth, the better. And if you don't expect them to be sold within your lifetime, a taxable account will work almost as well. Otherwise you're paying regular income tax rates for stock growth.