We're also forgetting that the Maverick at this point also has:
Medium Armor and Shield
D8 Hit Dice
Tool Expertise
Six Artificer Infusions
Access to Three Class Spell-Lists (Artificer and 2 others)
That's a whole lot of versatility outside of and beyond spellcasting.
Plus, 9th level brings the Maverick to whole other level of versatility, being able to swap out a prepared spell on the fly, and up-casting 3rd level spells to 5th level. Oh, and access to a FOURTH class spell list.
I daresay your problem is not with the Maverick specifically, which has some of the most exceptional versatility in the game. Your problem is with half-casters in general, and their perceived deficiency compared to full casters. Which isn't totally unfair, but 5e is not 3.X; full casters are not the overwhelming dominating forces they once were.