I wanted to try and post something about a natural progression but as you've seen by now, there is no such thing. What you really need is a good mentor. There is nothing better than brewing with an experienced brewer. You can see their equipment, see what does and doesn't work. Put your hands on a beer in progress without the responsibility of having to think ahead to the next steps or prepping when you've never done it before.
This is probably why it took me years to try AG. Heck, if you are already doing full boils the only thing you have to buy is an MLT. You can make one that will last a very long time for $40. That's less than the cost of 2 extract kits. I would say if you are interested but don't feel ready go for it anyway. It's better to try a little too soon than to keep questioning yourself.
I am getting ready to teach a friend how to brew and since I'm AG brewing now that is all I plan on teaching. I'm sure that within 2 or 3 batches he'll be good to go on his own. He just lives down the street so it might just turn into a joint venture! Yipppeeee....