Move the points from Runic Affinity and Scout to Inspiration
You shouldn't be taking the buffs and assuming you have Sweeping Lens if you can't sweep the ward with the normal range you won't be able to autoattack it anyways.

Move points from Enchanted Armor to Block and Unyielding . You only have 2 tank items so it'll provide like 5 armor and mr :L

No point in getting Luden's Tempest if you barely have any ap. I get that you love movement speed but this item slot can be put to better use. Especially since Luden's Tempest is pretty expensive.
=>I would recommend Mikael's Blessing. Assuming it's used properly it can be of great use. Especially on a disengage support like Janna

I don't know about Blitzcrank being so low on the matchups. If your adc gets pulled there's little you can do. If you get pulled you might be able to use a quick short range Howling Gale but chances are you'll probably die or lose a hefty chunk of health.



Just a few points I thought I'd put on there. Guide could use improvement but I expect you'll slowly update it over time :P

I think you need to be very careful calling this an aggressive build if you really only have 1 AP item in your most aggressive build. On top of that you also decide to scale up your core supporting skill first over your aggressive skills. You are basically just creating a standard Janna build but you decided that you really like Luden's Echo as an item so you threw it into the build.
I know you have abyssal scepter in there as well for ap, but in truth the magic resistance reduction of it is generally going to be out of range of Janna's Q(the source of most of her damage)

As for the guide itself... I know it's new so just keep working on refining it and then when all the information is clear and concise ask someone who designs sig's and pictures to help you make your guide all shnazzy.

I wish you all the best with your guide :)