I would like to see "Roll a natural 20, do double damage."
The groups I currently participate in use this rule.
I would like to see "Roll a natural 20, do double damage."
However I do know that in the Fourth Edition, skill is somewhat reflected din criticals. There are some feats to increase your critical range to 19 & 20. Furthermore if you are a poor fighter, and you cannot hit a tough monster normally, then a critical hit is only a hit (which you could not get otherwise). I think that is enough differentiation for now.
It makes sense, but I don't think they'll make that the rule. It's brand new and they seem to be looking backward for inspiration.
I would like to see a natural 20 is always a hit, no threat rolls, and DM's/player choice of bonus.
Example:
I would like to see a natural 20 is always a hit, no threat rolls, and DM's/player choice of bonus.
I think to combat hp bloat, crits could be nat 20 for max damage. An add-on to the rule is that you only get crit damage if a nat 20 plus your modifiers hits the AC needed. If not, you only get the automatic hit, not the crit.
If they do this, I would also recommend getting rid of all damage dice that are additive in favor of flat-distribution dice.