If you are using Docker on AWS then EC2 Container Service (http://aws.amazon.com/ecs/) would be an option. It's still in beta but looks promising.
It takes care all of the cluster management, launching, stopping etc.
I recommend Fastspring (http://www.fastspring.com). Yes, it's more expensive than others but it has a lot of features that make it worth it.
The main selling point for us was that essential you sell your product wholesale to Fastspring and they become the seller. This makes accounting and taxes much easier, especially for EU customers.
It's actually $9/month for Heroku Basic DB plan and $20/month for SSL endpoint not cert (you can use your own domain and SSL cert).
You can always piggyback on yourapp.herokuapp.com for free SSL cert.
Not to sound rude but what's your experience with project management ? Have you been a project manager or somehow involved in projects ?
How are you going to solve a problem that you don't know anything about ?
Originally it was developed for a final thesis about agile project management. Launched in September last year, totally bootstrapped and already have paying customers.
Pricing is based on the value it's providing. It is not a horizontal tool but deeply vertical. We are not competing with price and also not directly with Basecamp or Trello.
If you need more vertical stuff then check out Breeze (http://letsbreeze.com), it's Basecamp and Trello mashup. Plus it adds calendar, time tracking, budgeting and reporting.
They provide 3x512MB gears for free and you can use your custom domain.