I don't know if I want to go back. Do you mean Hide vs. Spot and Move Silently vs. Listen? As opposed to the 1-2 in d6? Or do you mean the possibility of losing up to two rounds of combat because of surprise? It worked fine until you brought in Dark Elf Rangers vs. Svirfneblin Monks or something like that (I know the second was illegal by 1st Edition rules) and you needed the article "Surprise!" in Dragon Magazine 133.
No I wouldn't wan't to do anything that primitive, but I would like to figure out an elegant way to give one side an advantage if they achieved surprise and the other side a disadvantage if they were caught off guard
Here are some of the considerations I'd like to encompass:
1) Surprise should give the "surprisER" an advantage, but it should not mean the "surpriseE" is literally paralyzed. Players should still have options, even if it's only to run a few steps back.
2) Skills like what I think they call now Stealth and Detection skills in Pathhfinder should play a role, but circumstances should play a role too. Which means it has to be at least partly subjective (i.e. up to the DM) but not completely open ended / undefined.
3) There should be a concrete circumstantial advantages in avoiding surprise. I think pretty much any time a PC states that they are expecting trouble that should count for something. Position in the line should count too, as should things like animal companions (one of the primary reasons to have a dog in real life is that they warn you when trouble is coming...)
4) There should be surprise in how surprise happens, i.e. it shouldn't always go down the same way.
5) It should be relatively simple to determine, preferably without charts or miniatures
I don't even know if all that is possible to work out but I'd like to try
G,