Honestly speaking there was never really any other choice.
Zeke wanted everyone to simply die off, a pitiful death but a sacrifice so that the rest of the world would continue on without them. However this certainly wouldn't end the war with Marley and the other countries which would inevitably continue. If anything Marley would have then become the next Eldians since they'd have entirely lost their manpower and would no doubt get fucked over by the countries that they'd dominated previously.
Giving into Marley demands would just continue the enslavement of the Eldians. Which is a non-option.
Threatening the Rumbling would only delay the inevitable war. But this would also force the Eldians to take on the same sins as the Marleyans and their ancestors by perpetuating a cycle of giving birth to childrens to eat their parents and so on and so forth. Which essentially just kept the wheels rolling on the exact same situation.
So ultimately I'd have to agree with Eren in a way, kill all of the enemies until there's nothing left.
Eren can't reasonably remove the Eldians power to Titan-shift until he deletes everyone else, simply for the fact that it would essentially be like dismantling your only weapon/defense.
Once the world is cleansed he can prevent Titans from ever existing again since their only use is for war.
However we still have an issue at hand which is that it certainly won't create a true paradise - war still exists even in a world of only Eldians.
So I wonder what Isayama intends to do from here.
I feel like the obvious answer is to have Eren give a permanent threat to the Eldians left behind, like saying "I'll be back if this shit happens again." And in a Code Geass-like ending, he winds up sacrificing his image to become the penultimate bad guy that the world both hates and lives in fear of. Alternatively he creates an outside force of titans to give a cause for humans to rally against, just like Paradise Island had done in the earlier chapters. A common enemy that unites everyone.