It will take some time for your legs to get use to the exercise, when I started I couldn't fathom doing 60 miles, now I do back to back 100 miles and think nothing of it. Just keep building on that 30 miles by 10% every week, or that is what many here will tell you. If you can do just that you will hit 60 miles in about 8 weeks. It may sound like a lot but it works. Recovery rides are essential to some, I will if I've had a real hard ride but normally don't bother with them. If you do keep it on the small ring and just spin around in your 19. As for recovery, a lot of that has to do with timing of food after ride, replace the glycerin stores with a banana, rice, pasta or something else starchy, along with some protein. Some swear by chocolate milk for this, I have found recovorite by Hammer Nutrition is what works for me. The most important thing is fueling yourself and staying hydrated when on the bike, think a sip of water and a bite to eat every 10-20 minutes if ride is over 1.5 hours.