Architecture: evaluate VPC endpoints and network topology impacts

We want to evaluate what's the (performance gain+cost saving) vs (cold-start performance impact+operational overhead) of introducing the usage of VPC endpoints (S3, Bedrock). It could potentially suck because customers would end up dealing with VPCs, NAT GW, ENIs for Lambda, subnets, but cost and performance should improve. We need to evaluate changes to the overall network topology and check if a NAT gateway is needed. A NAT gateway is a showstopper for me, because it's introducing static charges and defeats the purpose of a fully serverless architecture.