i know you're probably kidding but i would play the absolute shit out of a namine-led game. the only caveat to this would be that riku would surely be forced as the love interest (which is dreadful for a whole host of reasons...) but yeah, if all nomura is going to do with kairi is wave her around like bait and harm/kill her, he should honestly just go ahead and recast her role as Main Girl™️ with someone who a) isn't purported to be competent and capable of self-defense while in actuality being as fragile and vulnerable as a newborn kitten and b) has more narrative significance than "she's the love interest and watch her save the day with the power of being-the-love-interest"
edit: in no way am i trying to suggest that namine is absolutely perfect in aspects a and b (she did essentially epitomize the role of captive princess in CoM and sora/riku arguing over who got to be her bodyguard was essentially the whole plot of the story) but she does possess massively powerful magic that gives her the ability to effectively scramble brains and with that power she's able to heavily influence the plot on multiple occasions. with a little bit of work in the not-damselling department, she could easily become the strongest female character in the series. or, in other words: sweet angelic mind-bender baby.
I'm semi-kidding but personally I'd love it too because Namine is my 2nd favourite girl in KH franchise. Even though she's only got a limited screentime, I liked her tragic arc and despite being more...demure, I often feel like she's pretty much no.2 in terms of being a silent guardian who watches over Sora's journey in CoM/2, just behind Riku. While I like Kairi too, Kairi is... a character I like only because of her relationship with Sora, whereas I like Namine's individual character a whole lot more.
Plus personally, for her limited time in KH3, I loved the little bit of role she played ( influencing Lingering Will to come to fight Terranort ) and the part where she said "I got your back" to Sora was really cute.
I wouldn't be against Riku/Namine personally. While I like Sora/Namine better, that's a dead ship for more reasons than one and I have no real feelings on Roxas/Namine ( felt like that was a legacy thing back when the series didn't decide on making them their own characters ).