Like I stated previously 50%/50% portfoilio as a baseline is the way to go. There are many articles on the 50/50 and many pros and cons which I am not going into that.
However, within the 50% stock portfolio you should diversify into many different asset classes in stock: High caps, mid caps, small caps, energy, health, overseas, etc. The 50% bond portfolio shall also be diversify into many different bond classes: Treasuries, corporate, government, junk, etc.
During retirement, you are in the selling phase. I simply withdraw the stock or bond class that is relatively high. After that fund is depleted, I go with the next relatively highest value asset and so on. Remember "buy low sell high" and "diversification always reduces your risk".
I am selling the relatively high asset class during retirement. With blended or target date funds, you cannot do what I am doing. Blended or target funds works OK before retirement because you are not withdrawing. They do not work well after retirement when you need to withdraw and this is my opinion and I am not a financial advisor. Took me 40 years of experience to learn the real meaning of "buy low and sell high" and that portfolio management of your withdrawals involves a different strategy after retirement.
When I was working, I would sometimes reallocate my 50/50 portfolio in my IRA to 75% stock/25% bond after a correction/crash or to 25% stock/75% bond if the stock market reaches a high using the 50 days exponential moving average as a guide. You can do this without tax consequences in a IRA and this game is consistent with my "buy low and sell high" strategy. I do not play this risky game during retirement but it was fun for me playing this game while I was working.