I mostly spider rig, but have been learning more about how to longline. I think both methods are effective, but one may be more effective than others in certain lakes. If the water is pretty cool I tend to push slower, 0.3-0.5 and try to let the fish tell me what speed they want just like they do with using multiple jig colors. Varying the depth also tells you what they want. I try tipping with a minnow, crappie nibble or spray with Slab sauce. I don't necessarily do all three at the same time, but change things up and see if one is more effective. I carolina rig with a half oz wt to push slow. When longlining the speed is usually 0.8-1.0 mph. I will increase the weight to 1 oz and can push jigs that fast and still stay at the correct depth. I am not sure if this is more effective than pulling jigs, but I have less line out and can make sharper turns with essentially no risk of tangles. In my view, the primary advantage to pulling jigs over pushing them is the TM creates more vibration when going faster and pulling gets them farther away from the boat. Learning to fish with more than one technique improves success regardless which technique you prefer. Be safe and enjoy trying out new things.
Bill