[blueslurpee]

Interestingly enough, assuming you use React this is how I see the role of something like Remix[0], which serves as a "rendering layer" that aggregates application data from different API's/stores and then sends a cachable HTML representation to the client which is thereafter hydrated.

It's not quite a backend and it's not quite a frontend, but it sort of sits in the middle and (hopefully) helps you achieve lower latency. I haven't used it myself but I think it's a promising idea and based on your post I gather a similar concept worked very well for you.

0: https://remix.run/