Its not necessary that whole solution has to be serverless from start to end. Since serverless is in its nascent stage not all workloads can be shifted to serverless environment
Serverless has many distributed components so please be careful on observability and monitoring from start itself as implementing it later can become a nightmare.
If you want multi cloud architecture its better to use Pulumi or Terraform for configuration and management of your system.
If only AWS you are confident and going ahead with it, use AWS SAM and Cloud Formation for better access to resources.
As far as serverless languages go we would recommend NodeJS, Go and Python in that order as these have low cold start times and lot of community support around them.
We develop microservices based serverless systems where each service is set of serverless functions and does its jobs like retreving, updating, deleting based upon certain business logic.
No serverless is a broad term which generally means services are turned into functions and called as and when required. That's mostly backend part. Frontend remains same as we use React, Vue to access those services.
With serverless databases people generally think managed databases but there is a difference. For eg Amazon RDS is a managed database while Aurora Serverless is a serverless database
Serverless observability is possible. There are tools available like lumigo, Epsagon, X-Ray, Thundra which make tracing of serverless apps easier.
We provide flexible engagement models wherein you can try our serverless developer for a month and then extend for 3, 6 or 12 months with a contractual agreement. We provide 100% satisfaction guarantee in providing you with the best frontend development talent as per experience and skillset.
Although we stand by our technical expertise if you find any trouble we will provide you with a replacement and if still not satisfied, then you don't have any obligation to continue with us. Mutual happiness is what we thrive for. We don't believe in unnecessarily shoving contract up your throat.