Each reply has merit and I fish using some of them taking into account:
1. Speed never needs to be fast such as that used power fishing for bass. At one point the lure should entice at the slowest speed possible taking into account the lure's tail action. Hair or feather jigs require the least speed or manipulation to produce the magic flutter. My own design accomplishes that same flutter even when stationary beneath a float or nose hooked with dropshot. I've found finesse to be the deciding factor whether fish strike or not on most outings and the opinions expressed below attain that.
2. The combination of line test, lure weight and action and depth, are dictated by fish activity levels and they can vary from location to location and from day to day. Fish do appreciate lure action at most speeds depending on the lure, but some lures must be retrieved at a speed that allows a provocative action. Curl tail grubs, Beetle Spins, Road Runners and small crankbaits must be retrieved horizontally moderately fast, whereas the lure pictured requires the least amount of speed for the tail to flutter irresistibly. I'd go far as to suggest that when fish attack a lure, it does so not to eat it, but because the lure irritated it beyond its control to ignore it. Fish much of the time aren't actively feeding or in a feeding frenzy, so the other hours of a day are suspending, just hanging out. Here comes an object into its space - odd looking and acting, tickling its senses physically and visually - and that's all she wrote!
3. Line test need never be more than 6#. I like 2# test braid with a 4-6# test fluorocarbon leader which keeps the bow out. Light lures and heavier test lines work against each other and line bow is the result - an unnatural distraction from the lure. I'm not saying lures need appear anything close to a crappie's normal prey, but the key must fit the lock when it comes to a lure's appeal. Lure size, speed and action in combination make up that key.
4. Total Lure weight is mostly a consideration of horizontal casting or vertical distance. Plastic and lure weight (jigs) are usually enough together to get a lure to a point more than twenty feet away and down to where the fish are. No point fishing shallow when fish are deep and vice versa. Some lure depth will require 1/8 oz., but generally 1/16 is my choice for fish biting as deep at 10 feet or shallower. 1/32 is fine (along with plastic weight) for very slow speeds most fish can't deny when lure length is no more than 1.5 - 2".
So all and all, one size doesn't fit all (no pun intended) when taking the above into account. Lure size and speed are determined by the fish and generally I've found that slower is better in my 66 years of fishing lures. Last Friday I took a friend out for the first time and we boated over 100 panfish in six hours. He was a quick learner and blown away how simple it all seemed - even at age 55!
Sorry for such a long reply, but I get passionate about catching fish when the topic hits me and like to put ideas out there that may be helpful and considered novel in concept for consideration.