@Enzeru:
In that case his only chance of surviving in that world dominated by kings and strong personalities is– and this phrase is ever so appropriate-- to become their bitch and follow their will. In which case he might as well just go back to Daddy Kouen or Sin and continue doing their bidding.
The aforementioned 'showing of balls' does come with a few negatives naturally. We'd call it differently if it didn't. And one of those is possibly making an enemy out of a few people. Which is completely normal and part of being a king and leader of a country. There's always going to be someone who doesn't accept you.
Speaking of which; if Ali wants to save Balbadd he'll need to become its leader of some sort. If he wants the country to be independent and free of the Kou empire's soldiers, some kind of leader will be needed. Whether that be Alibaba or someone whom he himself deems worthy and who's accepted by the people doesn't really matter; at the end of the day Alibaba himself will need to take on some kind of leader/leading role. Which, and this brings us back to the initial problem, requires some balls.
Of course there might be some other solution that hasn't been revealed to us yet. But honestly, it would probably feel unrealistic and like an asspull. We have a certain situation at hand, we know the characters involved and what actions they'd normally take. Based on that there's not many paths left for young Alibaba to tread that would make sense in-universe.
It seems I forgot to address your problem of a power lack on Alibaba's side. That part can be solved easily if Aladdin makes one or two new dungeons appear. And by having Alibaba gain a few more followers or ideally a little army.
Now I haven't read Sinbad's stories yet, ( so I'm not really gonna mention him as I don't know his situation), but the general pattern in Magi for Kouen, for Reim, for all of Kouen's members who conquered vessels seems to be that they conquered the dungeons, or got the #'s of followers, or they inherited a nation, or Judar's helped, or Al Tharmen helped in their own ways but only afterwards and most of which was connected unfortunately in probably still as now unseen ways.
Alibaba on the other hand unfortunately also has the added bonus of knowing absolutely the consequences of any actions taken involving war. Now assuming he somehow completely overlooks this when starting some type of kingdom/ eventual dynastyand that absolute resulting mess of a mess, (which in itself would be a seriously bad decision for his future kingdom/ dynasty), any forces, or " small army" he could muster, somehow with great loyalty, with no actual nation, no slaves, and not composed of forces more loyal to either SinBad, Al Tharmen, or Kouen, even from after 2 or 3 more dungeon captures ( because realistically at most see him holding 4 Djinns and normally not even 4); I don't see them being them being 'effective' enough to really do anything they would need to do. Not protect even a small nations borders, not attack to gain new territory, definitely not to do both at the same time, nor to even add significantly to any of the other bigger kingdoms.
So now he has these forces, or small army, he's manned up but all he's done is gain some minimal forces and earned other nations mistrust, waryiness, and outright need to be destroyed. And we know what mistrust, regrets, waryiness, and need to destroy lead to, especially with a Kouen or some1 from Kouen's forces having just learned from their mistake with Hakuryuu, they'll either be afraid, paranoid, or outright antagonistic with every new force, once again leading to an opening from Al Tharmen.
Now I'm not saying Alibaba will lead a bloodless campaign, but to truly somewhat end goal be completely rid of Al Tharmen, he shouldn't be leaving a bloody trail that just gives Al Tharmen the fuel they need to keep leaving seeds of regrowth.
Then there's the matter of Alibaba taking back BalBadd forcibly in any way. That's what I would see as more of unrealistic, or "A$&pullish".
It's nearly the same as what Kassim did and Alibaba said it was wrong then, yet now it's fine because it's him?
It's like if when helping some1 move you first try to force a huge awkward uncomfortable couch/ refrigerator through the front doorway and stairs, and then you guys work out that it'll be better to do it slow and meticulously and figure a way if it's even possible in any way into the doorway without breaking the doorway , and the couch into pieces. Then after a while you just decide to force it thru, ( and surprise surprise it's way too forceful), breaking the doorway, parts of the couch, the light fixtures and scraping the wall, damage you will now have to paying a lot for something that was not even necessary, thus for no real reason.
So Alibaba mans up and forces his way into power in Balbadd, assuming the actual citizens don't immediately regret that as he still would have no resources of his own on his own, as that 's where'd he be if he forcibly took the place, a definite enemy/ traitor at least to what remains of Kouen's forces, (and assuming for whatever reason any and all of Kouen's forces have already evacuated Balbadd ), what's he really doing after that besides defending?
Just saying if he wants any chance of survival and winning in the end on all fronts with as little losses as possible, yeah playing" the bi&$h who gets tossed around, to either of both great kingdoms/ empires/ dynasties for a while", seems the best way "For Now Until He has managed to get make some progress into getting what you mention. And doing so despite probably every instinct telling him to do the opposite, and stupidly fight no matter what, would be a different but equal form of "manning up".
@Razh:
Like I said, it just seems that too much stuff would need to happen in order to elevate Alibaba to the status of a full fledged king. Seems like, whatever he choses, he's going to be someone's bitch, as Enzeru says. If he marries Kougyoku, he's under Kouen, if he helps Sinbad and gets back Balbadd, he's under SSA. Being the person he is, betrayal is probably out of the question.
Something big needs to happen in order for his status to change that much or it should happen gradually. If it should happen gradually, it would take way too long. I think I would actually prefer some kind of time skip, not unlike the one in Reim, where we only got to see Alibaba's first fight and only heard about what happened in between (like drawing Muu's blood).
Kou empire's civil war seems like it could take a long time. And while Kouen is busy with Hakuryuu, he can't direct his attention to Kou empire's expansion, living Alibaba an opening to elevate his game. I think the story could actually work a lot better if there was a skip, than if we had a gigantic battle, not unlike the one at Magnostadt. Alibaba has a lot of potential allies, but nobody is going to follow him the way he is now, that's for sure.
If the civil war could take a while, then it wouldn't be like the one at Magnostadt, right?
I think this one will be much more focused on the individual soldiers and forces Hakuryuu is controlling so he has no 1 to shield him when the more powerful forces come, but I think that Al Tharmen might send actual people to fight, a change for a slightlychanged in her methods Arba. This would also work to possibly to collapse any confidence Hakuryuu got from her defeat making him ripe to be fully corrupted and made into whatever the would slowly want to use him for over time.