I think the significant difference between a drawknife and a spokeshave is that the drawknife is just a blade with handles on the ends, nothing to keep the tool from digging in but your skill, while a spokeshave has a blade in a body. You've got a traditional wood-body spokeshave; the cutting edge presents at a low angle, almost flush to the wood. The other common design, with a metal body, is more like a really short bench plane with handles on the side, although this statement's a bit simplistic, since metal-bodied shaves also come curved front to back or side to side.
Woodworkers who get deeply into this stuff talk about wood-bodied shaves being better on end grain, metal-bodied on long grain.
Spokeshave blades/irons tend not to exceed 3" in width, with larger shaves, like the cooper's shave, having longer handles to clear the work, while drawknives tend not to be narrower (cutting edge) than 4", with the common sizes being 8" to 12".
Although it all gets very confusing when you get into the specialty trades like coopering and carriage making, where all bets are off. But these tools are rare.