Criticize the configuration on AWS. Is it balanced enough?

Question

Amazon Web Services

I'm going to switch to cloud hosting. In the future - distribution by georeferencing, for now, just combat and virgin. Load of 5-25k uniques on sites + about 20k requests for a writing script in the database (log of actions of users of the product). Sites live behind the Incapsula firewall/CDN, which slightly reduces the load, but in the future there is an idea to abandon third-party systems and raise your own proxy with a cache and load balancer by geolocation (minimum response time is important for the product).
I think to take 2 EC2: combat t2.medium and dev t2.micro. Both will connect to a database on RDS db.t2.small, EBS storage (scripts, etc.) and S3 (backups, pictures, videos, etc.).
I know that the database can be raised on EC2 itself, but on a separate insta it seems to me safer and faster.
The total is $600/year.

Answer 1

Are there many points of failure? Judging by the configuration, even the web server is not duplicated.

Answer 2

t instances have unstable cpu when you eat cpu points what will you do?

Answer 3

You definitely need a balancer and autoscaling. Instances are better to take not t2, but m5. If we want to save - https://github.com/cristim/autospotting.
Amazon has a CDN - Cloudfront. It is perfectly configured both on S3 (for statics) and on a regular domain -
Amazon has Geolocation for caching dynamic pages and goes through Route53. You can also configure failover there, but then it will obviously not be 600 bucks a year