As jaggederest said, you're not the target customer for Heroku. They are interested in hosting apps that have thousand's to hundred's of thousands of visitors a day for companies like RapGenius who don't want to focus on managing servers. It seems like you don't realise that Heroku is giving you a free dyno to run your apps on. If what they're offering for free doesn't fit your needs that's fine but don't be ungrateful about it.

I don't see what's wrong with pointing out deficiencies in the free tier. It's not as if Heroku is giving devs something out of the goodness of their hearts. It's part of their business model. He's just telling us that he doesn't use Heroku for his projects anymore because their dyno's take so long to warm up. I don't work at Heroku but I think their strategy is to make it a great / cheap platform to start an app on so that you pay them when your app gets traffic and needs to scale. If the free offering isn't compelling then the freemium business model doesn't work.

You just need to ping your website every minute. Pingdom or the like works just fine.