Being centralized doesn't mean it is not crypto, remember blockchain tech or related technology can either be centralized or decentralized.
XRP is an cool altcoin is you are using it as a fund transfer method. I don't give you a suppose to transfer all of your crypto fund by convert them to XRP and use XRP to move your fund. It is risky. Replay attacks can happen and you can lose your money.
If you are considering to move small fund (small part of your fund too), XRP is a good tool that gives you fast transaction and cheap fee.
Anyway, I used to hate XRP because of its centralized nature but the more I use it, the more I am beginning to like it because of its cheap and faster transfer than other popular cryptocurrencies which fits small-time gambler like us that think 10 min + of waiting is too much, and more than $2 transaction fee is too high. Also, Doge can be used too but many third party exchange in my country does not accept Doge for fiat conversion.
XRP is very economic, indeed. Many people loved and invested in XRP, kept their belief in XRP for years and they hated it because they lost their capital by their investment in XRP.
Dogecoin is good too but it is not supported on new exchanges. Dogecoin is a very old altcoin and you can find it on old exchanges and crypto gambling casinos but on young exchanges you won't.