Reading through the biblical passage, its difficult to imagine how everything fits together and if I had been set the task without any tradition to refer to I don't know where I would start. Looking at the various traditional images, artists seem to pick up on particular details and represent those and do not seem to try too hard to create a single picture with everything present. It gives me the impression that perhaps what Ezekiel is describing may not be a steady image, but shimmering changing picture in which different things stand out at different times.
One thing that definitely doesn't come to mind, however, is a podgy baby. Quite how the figures of the Renaissance and the baroque equated these with any descriptions of cherubim from scripture I don't know. Perhaps there is a passage that I am unaware of that leads one in this direction artistically? If so, I am confident that a New Liturgical Movement reader will be able to direct me to the right place.
And then, even if we've established that we can employ this form, we have to be careful to distinguish between putti and cherubs. The source of this style of image is, as with all the art of the High Renaissance and baroque, classical sculpture. Putti are impish, 'little men' that are based on figures such as Eros, non-material beings with mischief in mind. By the baroque era cherubs were represented in exactly the same way. The distinction was simple, if the painting was sacred, then the person was a cherub, if is was secular/classical, then an identical representation would be a putto.
Regardless, this isn't something that will engage my thoughts for too long. I have no intention of representing either cherubs or putti in the baroque style. Much as I admire the baroque, this is one aspect I am not pushing to see again.
I'm going to stick to trying to paint wheels with wings and eyes made out of chrysolite -- however hard that may be.
Images: first two, iconographic wall paintings (I'm not sure precisely where they are); third: Christ in Majesty, 12th century English with four cherubim shown, each with a different face visible.
Below: Bacchus (putto) and perhaps the most famous cherubs of all, in Raphael's Sistine Madonna