If you want to keep your privacy intact, you need to enable "Coin Control" in your Bitcoin Core wallet (it's in "display" options, enable "Coin Control features" (tick the box) then on send you will see "inputs", click there and then you can choose how you exactly are making transactions.
Send the coins in a proper way that it doesn't jeopardize your privacy.
For example if you are receiving donations in address A which is a public address, and you have a business that has address B which is also public, you don't wan to send A+B in a row because people would know you are taking donations somewhere. This is an annoying aspect of Bitcoin, you must have control of these things, I wish I could simply "click send" and be done with it, but it is what it is.
If you don't care about that, just send it all in a row in a single transaction.
And no, there shouldn't be really any "risk" into submerging all your bitcoin in one transaction, to one adress.
The risk is your privacy. If you own a total of 0.1
BTC, I wouldn't worry about it, and add it all together into 1 address, to safe on fees in the future.
But if you're holding a large amount of money, you should keep different addresses and smaller portions to pay for stuff. You don't want your local coffee shop owner to know you hold $100M in Bitcoins.
To safe on fees now: if you're not in a hurry you can set quite a low fee, and just wait for it to confirm someday. Or check
this fee estimator and make the transaction when it says 40 sat/byte again (probably on a quiet Sunday).
Well, if you have $100M in a single address and you wanted to pay for something without directly sending from such an huge address, I guess you can create a new receiving address, send a decent amount like $1000 bucks to yourself on there, and use that address from now on to pay for stuff, this way they couldn't prove you own $100M, just $1000.
