It will be always a good idea to diversify your investment into various coins so as to gain more profits and cut losses. The altcoins you have mentioned are good investment. Some of them are very much good investment while others are average. I want to add some other coins like Bittorrent, Beam, Huobi token. You can diversify your investment into these coins.
I have a lot of BTT in my portfolio, but every day I look at the price of this coin and continue to get upset. I bought BTT for 16 sat and now this project is getting worse and worse and it is not developing
Great, don't worry the complete market will stabilize when the market starts recovering. So BTT is completely in a downtrend if it is possible for you, better buy them in order to average your previous purchase and it will help you to make a profit when the prices start recovering.