My advice for what it's worth is one establish the best course you can afford,and then get your head straight back into principles of flight at a very basic but indepth level.Can you sell to someone the theory behind vx/vy etc.
You have done a great job of passing the atpl exams which gives you great KNOWLEDGE but is your UNDERSTANDING up to speed on the basics?
Their aren't many careers where people come straight out of Uni and go straight to a front line job,a doctor for instance so take instructing as your building block or apprenceship for your chosen career.
Some instructors might not agree about it as an apprenticeship but i like them would be straight out the door if offered a jet job!
It was the best advice i had to become an instructor and you won't earn a mint thats for sure but you will be a more rounded,more switched on pilot than you ever were after passing the CPL flight test or IR.ENJOY