Do not buy into the hype that all grain beer is inherently better than extract. All grain brewers are typically more experienced brewers than extract which leads people to believe that all grain beer is inherently better. Its not the process but the brewer.
This is it. I brewed for 2 1/2 years using extract before I made the switch to partial. I did that for 6 months to get used to the mashing process by using a 2 gallon cooler. Then I made the jump to all-grain. By the time I was going all-grain I had a pretty good grasp on things like yeast health, temperature control, cooling, basic mashing, specialty grain flavors, etc.
I invested in kegging and fermentation temperature control long before I switched to all-grain. I'd recommend looking at those two first. Kegging allowed me to pump out more beer and my fermentation temperature helped me nail down consistency in flavors - which then allowed me to experiment with different things.
Another thing to look in to is full boils. Not sure if you're doing that or not, but that can help out early on. Boiling 2.5 gallons on the stove is a lot different than 7 gallons on a propane burner. You can pick up a cheap 10 gallon pot and fit it with a ball valve. That equipment can be used with all-grain if and when you choose to step up.
My first couple all-grain batches were worse than my extract batches. It takes a few brews to get your process zeroed in.
One more thing to look in to is getting the freshest extract. Austinhomebrew liquid extract was always my favorite. They have such a high turn-around that it's almost always fresh. I was never a fan of dry extract.