Well Sona was my favourite main long time and...WHAT? u just said that you are always attacked by all enemy team???That is surely because of only few hp bars so you are just flying around gold xD

As you can see I max out aria first, followed by hymne because I see myself more as a supporter than as a real damage dealer. But that totally depends on your preferences, that are just mine.
Actually, my games with her don't even last long enough to get by the Deathcap, but the Heart would be a good alternative. I tend to end up playing very short games or having an enemy team way better than mine (bad luck I would say). It's a rather offensive guide, because normally I'm attacked by a whole team and nearly instand-dead, so I didn't care much about resistence and so on. And I also think that such decisions depend on your own playstyle and preference, I never said that these items are the only possible wants - if you want to be more durable, buy different items - it's your choice.
The point about Greed is true, I left the masteries as they were when starting playing dominion, but you are right that it won't be very useful in dominion.

I'm very glad you left a comment after voting, but also disappointed that you disagree that much with my ideas...

Well i more like leveling hymn together with aria because it is your only damage spell(not counting ulti),plus hourglass wont save you against autoattackers frozen heart is beeter and it gives nice cdr,some magic resist would be nice too or you will be just too squishy for Katarina, Ryze,or even Kayle and greed is totally useless is arguable in normal matches and useless in dominion.Match is going 20-25 min mostly, so it is 90-120 gold in game where you are gaining insane gold amounts,just not worth.