I don't think Best (or Good) will be Free, after a certain tier (e.g AWS only gives a t2.micro for a month (750 hours to be specific))

Most of the cloud providers have some kind of startup program, where they offer free credits to startup.

We (my company) got credit benefit from IBM, it's been a real savior for us. You can check it out here https://developer.ibm.com/startups/