Flat AP or AP scaling on support sona?
Ap quints armor yellows mpen blue ap scaling reds
or all flat ap plus armor yellows
Which is better for early game harass?
I start spellthiefs and hp/mana pots.
Ap quints armor yellows mpen blue ap scaling reds
or all flat ap plus armor yellows
Which is better for early game harass?
I start spellthiefs and hp/mana pots.
I take flat AP on my AP supports. Sona's strength is her early game Q harass, and flat AP will get you more benefit there than scaling AP will.

Which is better for early game harass?
Flats are always better than scaling for early game. The whole point is early power that falls off almost immediately.
I start spellthiefs and hp/mana pots.
Marks are the best runes to use for penetration. Since you're focused on early harassment, I recommend Hybrid Penetration. They're almost equivalent to the MPen you already had with Glyphs (0.62 vs. 0.63), and add some APen for your AAs/Spellthief's Edge. The Tribute proc will do magic damage when you Q, and physical damage when you AA. I personally prefer using Glyphs defensively for MR, but you can use those for AP. Flat AP Glyphs are roughly double the strength of AP Marks.
I run movespeed quints. I find that really useful later on in the game, when you roam around to ward.
Supports = always FLAT AP
Reason :
As a support at early game you need have dmg / poke etc .
At late you game you are not Carry so you don't scaling runes. At Late game you provide some sort of CC .
i take hybrid pen marks on sona. a lot of her damage comes from her empowered auto attacks so the extra pen on physical and magic damage helps a lot, especially if you build sheen/lich bane at any point.
the blues i take scaling ap as my preference.
Scaling is really only useful if you plan to be a big damage dealer come lategame. Because Sona is a support, you are typically looking more for utility when late game comes, so it's best to abuse her early game damage with flat AP than with scaling.
Unless you're ALSO building straight AP with her, you won't be dealing much damage, so you're better off taking the flat.
In my opinion mana regen glyphs are stronger for long term sustain/poke and cooldown reduction glyphs are better for maximum [base] damage output, although AP glyphs are a good compromise.
Sona's strength is outlasting her opponents however it's gonna take a while to squeeze out the worth of mana regen glyphs. Also fun fact, flat mana regen glyphs need 3 minutes to outdo flat bonus mana glyphs so flat mana is about as viable too honestly even though they are hardly used.
Generally though it's smart to stick to magic resist glyphs if they have magic damage threats. Most supports and some ADCs even have magic damage. Corki ADC does a lot of magic damage for one
That's glyphs in a nutshell
I just checked though and Sona has extremely good AP ratio's so I would go with AP or MR
I'm only gold and don't play support very often, so my idea might be wrong. I'm an aggressive laner and this seems to work well enough for me:
2 Movespeed Quints 1 Armor Quint 9 Hybrid Pen Reds 9 Armor Yellows 6 flat AP Blues 3 Scaling MR Blues
I've thought about switching the movespeed to health, but never got around to doing it.
I actually go with this set up for my AP style supports
Flat AP Quints Magic Pen Marks Health Seals AP Glyphs
Mpen reds are better than mpen blues. And AP blues are better than AP reds. So no matter if you decide on scaling/flat you want to switch those two.
I go with:
Scaling Health Regen Yellows Scaling AP Blues Hybrid/Penetration Reds Flat AP Quints
I start Dorans Ring for additional health and a extra ward. No need for pots cause runes and masteries. Warding Trinket. By Sightstone first, and swap trinket for Orb. I start building towards Liandry's and boots depending upon the game(Merc, Mobility, Ninja). I build into a Iceborne Gauntlet over Lichbane as the slow adds some cc needed to Sona. I finish with Tanky/AP items depending on the game.
For early game harrass? I'd start Flat AP Blues, Mpen Reds, personally.. But that's just me, and I'm by no means a pro - That just seems like it'd give you the most flat AP(Early game poke), with some Mpen(Early game poke).
Scaling AP isn't going to outscale flats until late in the laning phase(For a support, considering you'll likely be roaming sometime shortly after 6), thereby the flats would give you a much stronger poke(Consider Level 1-3 poke, Flats Vs Scaling, the flats blow the scales out of the water), and shorten the time it takes to get your ADC ahead(Allowing you to roam).
mpen blue ap scaling reds
Okay, no. This is the completely wrong combination of runes. Magic Pen marks, scaling AP glyphs. You get more out of both that way. Marks are good ad/ap pen, ad, and attack speed. Glyphs are better for AP. Also, AP scaling marks are really bad.... Scaling AP glyphs are the only good ones.
flat runes for support