This means a level 11 akali that is even with you will have a gold advantage of 2328.
Yes and no. Yes she gets 2328 worth of stats but you are also disregarding the value of the kit from other champions, and some are hard to calculate but here are a few a quick examples:
Vladimir with Rylais + Wota + Sorc Boots + Blasting Wand + Amplifying tome = 7795 gold
Vladimir gets 1841 gold from 7795 gold worth of items.
Yasuo with Statikk Shiv + Infinity Edge + Berserker Greaves = 7300 gold
Yasuo gets 2250 gold from 7300 gold worth of items.
Akali with Gunblade + Zhonyas + Sorc. Boots = 7760 gold
Akali gets 2328 gold from 7760 gold worth of items
So Akali's gold advantage of 2328 isn't exactly fair in these terms is it? In these terms Yasuo has a 382 gold advantage ... he spends 460 gold less than Akali and there is only a 78 gold difference between their passives. She would however have a 522 gold advantage over Vladimir but that is still a substantial amount less than 2328 gold. Also I didn't calculate the fact that Yasuo loses 10% crit damage from his passive or the value of his shield and I also did not include runes or masteries at all and I just used your numbers for Akali so I have no idea if you calculated runes + masteries into that but it would change things if you did. I'm sleepy and it's late so I don't feel like doing a ton of math all to prove a point but the jest of it is that you can't just compare the value of someones passive to every other champion as if they had a passive worth 0 gold.
That being said I think Akali's passive could be reworked it's honestly boring getting free stats that offer no gameplay so here is an idea:
Twin Disciplines
Disipline of Order: Akali deals X% more damage to targets below 50% hp.
Disipline of Chaos: If Akali falls below 50% hp she gains X% spell vamp and X% lifesteal.
This promotes a little more gameplay instead of just giving raw stats it also makes it so that gunblade isn't mandatory because of the efficiency which gives Akali a bit more build flexibility. I didn't include hard values because it's hard to tell what would be balanced without some tests.