What is the best Coinbase alternative?

I've been hearing a lot about Coinbase but am looking for an alternative with potentially better features or services. Could you elaborate on what factors I should consider in evaluating a Coinbase alternative? Specifically, I'm interested in security, user-friendliness, supported cryptocurrencies, transaction fees, and customer support. Are there any platforms that excel in these areas? Also, what are some of the most popular alternatives to Coinbase and why are they preferred? Lastly, what steps should I take to safely transfer my digital assets if I decide to switch platforms?