An Eclectic Collection of Fun and Effective Builds

[LudicSavant]

I could see a case for doing it after 8. That's when you can learn Shadow Blade, and you've also picked up War Magic which means your cantrip/attack damage will continue to grow when you hit character level 11 even though you're only Fighter 9.

Fighter 9 and Fighter 10 are okay but not incredible individually, so you don't miss much by delaying them. Fighter 11 gets your 3rd attack which is a big deal, but you're mitigating that a little bit by continuing to use War Magic.

That could work.