For the record, I didn't pay Bubba to include my name with the others and be given such words as experienced, LOL!!!!!!!!!!!!!!!!!!!!!!! I do appreciate it tho Bubba, and will try to answer your question as best as I can.
Keeping this as simple and straight forward as possible, one can't and won't catch crappie in places where there are not any crappie. Same is true with all the different techniques, I believe that each technique has its own "season" per say, and one can take advantage of that particular technique and use it in areas that are holding fish, and have a reasonable chance at catching fish.
As we all know, crappie are and can be finicky and may change their minds faster than our little ladies at home, (love ya Littlemamma ). All factors involving water conditions, weather conditions, moon phase, time of year and day, technique, color, speed, and the actual conditions of the fish environment have to be taken into consideration. I believe one can take the proper heavy weight and spider rig in the summer, either over brush, stakes, or even working suspended fish or working topography changes to catch fish. Speed will be a factor so the weights will help in keeping your lines straight. This will catch fish, again one must be in the areas that fish are at before it will work. Again pulling or pushing cranks will work as well, so let's talk crankin'.
This technique is a very useful and enjoyable way to catch fish, it can catch a variety of fish, and keep you very busy as well. The above first principles of being in areas that are holding fish is key. One will learn alot about topography if you will listen to the fish, and interpret what the fish finders and the fish are telling you. Look for areas on your maps prior to a trip, like ledges, bowls, old ponds, road beds, pinch points, and even very nice big flats with the depth of water that you maybe focusing on. Use this pre-game information on the water to help guide you, and with what you might be seeing on your graphs, some previous knowledge, and some luck you might just find your pot of gold.
Also having a nice selection of cranks to choose from is critical, and one of the most addicting pieces of the puzzle. This also is where the manufacturers begin to smile real big, and wives begin to frown because crankin' aint cheap, but its very very addicting. It always seems like the colors are constantly changing with the angle of the sun, the amount of UV and the water clarity, so one will chase color alot of times. A simple difference in shading of a bait will make a difference. And then you have the speed factor. In my short span of crankin', I have not ran much slower than 1.5mph, so after the crankin' gets in your blood you will be on here asking us about batteries and how to run longer!! In my non-expert opinion, it seems to me that the most consistent action in relation to speed seems to be between 1.7-1.9 mph. So, this speed will affect your crankbait depth charts but no by much. And, I truly believe that it only gets better the hotter it gets!!
The other piece of advice would be to have some line counter reels in your rod spread. I currently run 8 rods and have 6 line counter reels, and the two most inside rods, 1 on each side, I use open face spinning reels and cast them. Everybody is different on this depending on their style and who fishes with them mostly. My girls like to cast them alot, so it gives them that opportunity to cast. They handle the line counters just fine as well.

In short, we all must remember why we do this, and its to have fun and enjoy the great outdoors. Each and every hobby, one must pay to play, and everybody has their own level of paying. Decide how much you want to spend AFTER you go out with somebody and get your cranking feet wet first. It might not be your cup of sweet tea, and will save you some money. I hope that I answered some or most of your questions, and if you have any others just ask away or shoot me a pm.