I'm going to begin my discussion of the 2019 rules changes by talking about the rule changes that give a break - things that are no longer penalties. Most of these I like:
1) There is no longer a penalty stroke assessed if you hit your ball twice during the golf swing. It happens - I've done it myself. You open up your wedge and try swinging under a ball with a good bit of grass under it and you end up hitting it again as your club comes up for the follow-through. No longer have to add a stroke to your score - you just have to accept where the double-hit ball comes to rest. No penalty. T.C. Chen's going to wish they'd enacted that rule 40 years ago....
2) Same goes for accidental deflections. You hit a tree in front of you and the ball comes back and hits you or your equipment (I've also seen this one happen to one of my teammates in league play when he hit our golf cart last year). Old rules would require you to add one stroke. No longer a penalty and you have to accept where the ball came to rest. Now, if it comes to rest in a penalty area, that's another story. If you can't play that shot as it lies, you'll have to use the provisions associated with that penalty area (red or yellow). If it deflects out-of-bounds, the ball's out of bounds and you'll have to replay the shot with a penalty stroke.
3) This is one I really applaud - it should have been changed years ago. It is no longer a penalty for you to accidentally move your ball during a search for it. If you do move the ball, you just need to replace it exactly as it was (or your best estimate of the original condition). No penalty stroke added to your score. It used to be that if another player moved your ball accidentally during a search that there was no penalty. I always thought the same logic ought to be applied to searching for your own ball.
4) There is no longer a penalty for hitting a flagstick (in the hole, attended, or laying on the green) when playing a stroke on a ball on the putting green. Adam Scott and Bryson Dechambeau have gone as far as just leaving the flag in for most or all of their putts. (Keep in mind that you have to decide whether the flag is in or out before making the stroke.) Hits the stick and falls in - no penalty. I don't know if I quite agree with that one, and I'm fairly certain that there may be some reconsideration on that rule. Just seems to me that some players are going to want the flag out, others in for a putt and you'll constantly be sticking the thing in and out of the hole. Instead of saving time, you may actually increase the amount of time it takes to putt out. We'll see!
5) Now, one caveat. We've been talking about accidental deflections and accidental strikes into you or your equipment. If you deliberately place you, your caddie, your equipment or the flagstick to stop or deflect a ball, 2 stroke penalty still applies. You can't lay the end of the flagstick next to the hole and let your ball ride the stick into the hole. That's an egregious misuse of the stick and goes counter to the spirit of the game.
6) It is now no longer a penalty for carrying a non-conforming club in your bag (assuming you're not carrying more than 14 total including the non-conforming club), but you will assess yourself a penalty of two strokes for every time you use it.
7) It's no longer a penalty to remove loose impediments in a bunker (as long as the ball doesn't move as a result) If that stone bothers you - remove it!
8) You can touch the sand in a bunker with your hand or a club (you can now rest clubs in the bunker if you wish) AS LONG AS you are not testing the sand's condition, or you're not executing a practice swing. You also still aren't allowed to ground your club directly in front or directly behind the ball or touch the sand in your backswing. You can also now lean on a club in the bunker while you wait to play (as long as you're not near your ball position). Seems to me that all that's really changed here are the allowance for accidentally touching the sand or touching the sand to remove loose impediments. Still hover over the sand in your backswing.
9) You can now slam your club in anger against the sand of the bunker without incurring a penalty. I know quite a few people who will be taking advantage of that!
10) It is no longer a penalty to substitute another golf ball when dropping or taking relief. You can certainly use the original ball, but you don't have to. Ricky Fowler could have used that during his first Ryder Cup!
10) Here's a radical departure. You are now allowed to ground your club without penalty in a penalty area. You can even take a practice swing in the penalty area and touch either ground or water in the penalty area on your practice swing or the backswing of the intended stroke. You can even move loose impediments in the penalty area WITHOUT PENALTY! You can't improve your lie or condition by breaking growing plants or trees in the penalty area, nor can you seek relief for an embedded ball or immovable obstruction in a penalty area, but just about everything else has changed in there.
11) There is no longer any penalty associated with fixing damage on a putting green (edges of old hole plugs, shoe or spike marks, scrapes or indentations), but do it without wasting a ton of time. Aeration holes, however, are not damage and are part of the green's current condition. If one of the aeration plugs is resting on top of the green, it's a loose impediment and can be moved anyway. Same goes for a diseased are of the green or a dead stripe in the green caused by faulty equipment - play on.
12) It's no longer a penalty to walk or touch your intended line of putt. Just don't change the putting surface deliberately to influence the putt by doing it.
13) There is no longer a penalty for using a damaged or altered club during the play of a round, even if the club is damaged in anger. However, if you deliberately damage a club, you cannot replace it for the rest of that round.
14) I've never used a caddie, nor have I seen one used in REGL play, but caddies can now mark and replace balls on the putting green without penalty.
15) No more need to establish local rules to allow the use of Distance Measuring Devices unless you're playing in a USGA tournament, there is no penalty for the use of such devices anymore.
I may have missed a few more, but it's a good start. Remember, the intention is to simplify the rules and allow for quicker play. I hope we can use that to our advantage as we begin league play!