I have a KA (the smallest one!) from 1985, still running, used daily.
I make 2 loaves every 3rd day, plus the occasional bagel and pizza
dough. I crack grains with the grain mill attachment several times a
week. All of which is to say, I am a heavy KA machine user.
My solution (very cheap) has been to get an extra mixing bowl.
Depending on the load, I divide among them. Digital scales make this
very simple and fast. The level of effort is very low, the result
quite good. I have no trouble with 2000-3000 gram batches.
Once you right-size the load to the machine the problems with oil
seep should stop. And perhaps equally important... learning to batch
across production need is a useful skill.