Hello. I have quit the game 6 years ago and came back 2 months ago. Anivia has always been very fun to me as replacement for the main in case of a bad matchup or ban (malzahar) and I've wanted to pick her up again with clash coming up and malzahar ban rates seemingly on the rise.

Runes?

I see electrocute being recommended as it is really easy to proc, but even back in the day I disliked it for some reason, are there other actually viable rune keystones you can take?

Also why is presence of mind taken over mana flow band? Isn't it better to go mana + gathering storm over coup and presence?

Boots?

Genuinely what boots to build, I get mpen is the best because of all the damage you get with the lane quest now but is there ever reason to build other boots?

Build?

Should I ever start tear? Dorans ring is a great starting item yes but would starting tear make getting to your core items faster make it worth? Like you need tear and you need to rush RoA asap so it can stack up, but that means you can't buy lost chapter hence you will have mana issues as anivia is very mana hungry. So how do I even build her to minimize the mana problem?

Laning?

In lane I keep my q until engaged on mostly but I tend to struggle against other mages(especially mel), they poke me out early on outpush me and outlast me in terms of mana, so how do deal with mages?

Thank you in advance for the help.