Dataloader (https://github.com/graphql/dataloader) eliminates many n+1 issues. Basically, entity requests are queued up during evaluation of the query and then you can batch them up for fulfillment. It’s a great addition to other asynchronous contexts as well.
WRT random requests, there are libraries for query cost estimation you can use as a gate.
WRT random requests, there are libraries for query cost estimation you can use as a gate.