Is it worth taking care of anonymity too much, even if I won't be using cryptos for any illegal matters?[/b]
If you don't use it for any illegal purpose and you don't care about paying taxes, I think this will be fine, you don't need to worry about it. Typically, cryptocurrencies will be used for large transactions and for dealing with people with geographical distance, this will reduce transaction waiting time as well as avoid taxes and fees. But any transaction used for tax avoidance is illegal, meaning you have to remain anonymous.
But there are some cases that you have to comply the requirements of your local exchange regarding KYC, you have no choice but to use them when you convert your crypto to your local fiat. Unless, you will use some P2P transactions to exchange your crypto, and this option is sometimes too risky. Maybe just submit your docs to legit merchants if you can't avoid the KYC thing.