I always do Burgener (snatch) warmup w/ a 45# barbell for 5 reps of each (BTN press, pressing snatch balance, heaving snatch balance, snatch balance, drop snatch, jump shrug, jump shrug+highpull, muscle snatch, power snatch). It's funny how even a light weight like that can get me sweaty and warm in a hurry.
I think there may definitely be value to assistance exercises with weight progressing up. Also, possibly set the criterion for "making" the lift be performing the portion that you're doing wrong correctly.
For example, I have the tendency to not finish the second pull if I get under the bar properly or hyper extend when I do finish the second pull. The criterion for the first would be hitting full extension (similar to clean high-pull). The criterion for second would be just rack the bar with appropriate forward lean + knee bend + elbows. Is there a clean equivalent to drop snatch?
Maybe I'm overthinking this a bit.