I'm still learning myself, but feel free to post something. If I don't see something, maybe someone else here will. Also a clue would be in chrome dev tools, Network tab, if you see long running requests... its no bueno. Building Asynchronous software takes intention though...

Maybe you should look into message queues... like RabbitMQ

Heroku has separate "work dynos" right? Maybe that's key, how to move work from your web dynos to your workers dynos?