Yeah, unfortunately the beastly impacts are M18 so different batteries than the smaller M12 tools. They do make an awesome M12 3/8" Stubby Impact. Anything bigger you need to bump up to the M18 line.
Milwaukee 12v is the bomb for most drill/driving/ratchet. Super compact, ergonomic, well built, and the same power as “20v” equivalent twice their size. It would be my number one choice for anything except larger impact wrenches.