ROF and the ability to keep a bait at the depth you want is important. I find sometimes a 3/8 bladed jig will rise on me depending on trailer and line and retrieve, but a 1/2 will keep it down better most of the time.
For jigs, I usually use 5/16 as my starting point. When I first learned to punch I would use 1 oz to 1.5 oz weights and I missed almost every strike if I even knew I had one. In order to really learn I started with a 1/4 oz-3/8 Weight or Jig to get used to the feel of that since you can put that through most cover just not as fast, but now that I have improved, I can just work a 1 oz weight faster since it falls right through, but faster falling lures often generate more strikes when a standard fall is not working.
In clear water I prefer heavy since I don't wan't fish examining a slow falling bait...I learned how to fish plastics on texas rig when young so Jig fishing was easy to learn, but I would get proficient with the Texas rig first, if bottom is soft you may not feel it, but learn to watch your line, and watch line fall to see how deep it is and then mark it with a marker, this way if your line jumps on the fall on slack, which sometimes is what they want, controlled is hard to always do, you will know you have a fish if your 6' mark is under water, fish is running with it...
Line watching is the best way to fish a jig imo if you lack confidence or have not learned to weight the jig. Any movement that is not normal is a fish, so swing......Under mats often suspended fish will travel from far away and want the bait pinned right under the mat, so always work it up to the top, control it slowly down and pause it mid way, shake a bit, let it flutter, then shake on bottom, pump it a few times, and when pinned I like to gently tap the top as if it was a bluegill eating bugs...Once you find a pattern you will gain confidence and start recognizing strikes and weights to use. Using really heavy Tungsten weights is hard, not all that fun, and you lose fish from popping open the mouth if not good at setting perfectly and on time...
Get in the habit of pitching with the hand you do not reel with. If you want to pitch with you RH baitcaster, with your right hand, I still do many days and it always comes back to haunt me at the worst times since you are fishing for only a few bites and they usually come in groups...2 hours with nothing and then next 20 yards you can limit out. Missing the first one can get you frustrated, I like to try to use 3/4 for punchiing with a worm to start...