I won't downvote yet. It's a good(maybe a little bit under good) guide for your first guide. Here are the things I didn't like and would recommend you to work on:
- First of all, while I don't care that much about it, most of the community appreciates a guide only if it looks aesthetic. Try looking into guides to make your own guide look better so you get a chance at getting one of the better guides this site has to offer.
- You say AP Ezreal is countered by MR. Every AP champ is countered by MR because that's what MR does, it reduces AP damage. It's just the same with AD champs, they get countered by armour because armour reduces AD damage. Whatever you build, the enemies will build items to minimize your damage, so saying MR is a counter to AP champs is redundant.
- Saying runes make no difference is plain stupid. Remove that from your guide asap. Runes do, in fact, make a difference. You will feel it only if you stop playing with runes. Talking about runes, you should offer alternatives(AP marks for instance seem fully viable to me).
- Mercury's Treads aren't usually built for MR, but for tenacity. If you still consider them bad, at least mention the fact that they give you tenacity in the "Items" chapter.
- Here's a question: why didn't you consider Zhonya's Hourglass?
- Divide your chapters a bit: make a different chapter for Pros/Cons and generally try to make more chapters so that your cluster of information is well organised.
- You may consider adding Match-ups.
- Make a chapter called "abilities" in which you explain the fine details of your abilities and at the same time provide information(videos even) on how to use them properly.
- In a new chapter, you should write about a basic game(nothing too out of the oridnary), explain what you do, why you do it, why you didn't do something that seems more or less logical, how you opened up objectives.
- Ezreal is a cruel champion, he punishes champs that are out of position extremely well. Try to tell your readers when an enemy is out of position and how to punish him safely(kinda covered in the "combos" part).
Unfortunately I can't check if the items/runes/masteries recommended are viable or not.
There may be things that I can't really detect now but once you finish dealing with these, shoot me a PM or re-request a review(just go to the shop and ask again). Also, if you can't figure out some things regarding guide aesthetics, just tell me and I will be more than glad to make your guide prettier.