I personally would brew a couple extract kits, to get the feel of the process doing something fool proof, and getting practice taking gravity readings and working on your sanitization. There are a lot more variables in AG brewing to worry about, from the beginning, if you don't get the crush right, or the mash temp right, you don't get the gravity right, and if you don't get the gravity right, then you won't get your hopping right for example.
Starting out simple with an extract with grain kit, especially if you do it as a full boil, and use your wort chiller, which folks usually don't start doing til they go AG, will mean that if something goes wrong, you'll have an easier time isolating your issue, rather than having 10 different variables to trouble shoot.
I think it's important to nail your process first.
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Why can't we all get along, for more of what I'm getting at.