Try keystoneJS, it doesn't have themes but the admin side is pretty solid.
Not sure why you're looking at headless CMSes if you want frontend and admin/dashboard.
Ghost is pretty good as a blogging platform and has theming support.
Thanks for suggestion. I tried keystoneJS too along with 20+ other cms solutions. Still these cannot impress me.
And all these conversation is about cms part only. There is the virtual dom, node_module folder, crypto mining, fatigue and other dark talks left to talk :D .
I think Strapi is great if your looking for an open source solution and maybe the best I've come across after testing many. It isn't without it's issues though. Saying that it appears to be well supported by the people building it so the future looks bright.
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