My personal favorite is EK 7/wizard X. That way with the weapon cantrips you get 2 attacks plus the benefits of the chosen magic, this is generally on par or better than 3 normal attacks you get at 11. Then you get all those wizard levels right that means. You get access to a lvl 7 spell selection, you get slot progression up to 15 so you get an 8th lvl slot. You get a complimentary arcane tradition, like evocation to drop fireballs on your own face, or abjuration to get extra free health that you can refill with the alarm spell for the cost of no slots. Plus all those spells in general, you're a wizard harry! You'll have enough ASIs to go around, and even enough to maybe buy a feat or 2.
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I'd definitely start as warrior for the extra HP, con saves, and it's almost a most for a strength build so you get heavy armor. You won't have as many hitpoints as other gishes, unless you're an abjurer, but you're not that far behind and you bash and cast really well.
Another build I sorta like is if I'm going to take fighter levels with a caster class in general, is to grab EK a lot of the time. Like with a gish warlock, to get access to the shield spell and the extra slots. But that's a more general thing.