However, this change, particularly the "tackler(s) must roll away immediately" implementation is making the definition of the tackled player being held hard to play.
What I propose is the following amendment:
The tackler(s) should hold the tackled player for a quick count of 3 (not 3 seconds, but counting in a normal voice and cadence 1, 2, 3, which is around 1 second). and must have released by the count of 5. The tackled player may hold the ball for a count of 5 from the time of the tackle, but must have released/placed by the count of 7.
Now, there is one obvious problem with this... the tackler(s) will find it much harder to roll away in most circumstances because by the count of 5 there will be a ruck formed around them. So, rather than roll away, that law needs a tweak too. Although the lawyers will have to look it over, something along the lines of:
The tackler(s) must release the tackled player. They must move as far as possible to clear the ruck area. Ideally this is to move away completely and return to their feet however moving their arms clear of the ball and moving so that their torso, arms and legs have minimal impact (e.g. lying on their back with their legs still and arms well clear of the ball and on the ground, granting clear access to the ball for the other side)
would do I think. Maybe with a reinforcement of "the tackler cannot actively involve themselves in the game in any way before returning to their feet."
Heck, with a little work, you could even restore rucking. You might not want to of course, but something along the lines of
Players may be moved from the immediate proximity of the ball by a predominately backwards movement of the foot applied to their body. Rucking must take place on the torso below the armpits, the central parts of the arm, forearm, thigh and shin. The rucking action must be controlled, with one foot clearly planted on the ground (no "rock climbing" style rucking) and must be safe in the opinion of the referee - clearly avoiding the head, neck and all joints
would work, don't you think? Maybe combined with making offences to the rucking laws clearly yellow card with a strong bias towards red cards for dangerous play should be included, along with the ability for the referee to ask the TMO for advice on rucking when he is not sure if there is an offence or of its severity. The TMO should quickly be able to rule on one foot on the ground, predominantly backwards movement, missing the joints after all. If all of those are OK, then you're really in penalty-only territory if you're missing the "near the ball" bit... which might be harder to rule on but the ref can usually tell that.
Overall, hopefully, it clears up a messy grey area and reduces the number of daft penalties... More rugby, less kicking at goal. Result!