There's endless decent alternatives, I've used outlook, hotmail, etc. I've even created websites to give me email options to go with my perceived online legitimacy.
most issues with gmail getting locked out are related to the quality of the IP
save your cookies/history and use residential IPs and you will almost never have an issue with unlimited gmails
if you are ever locked out and its asking to send the phone # a text, refresh the page after 30 minutes and try again with the same IP / same history/cookies and it will let you in majority of the time