What would 2e have been if the designers implemented their desired changes?

[Mark CMG]

I knew a lot of DMs who ran 1E adventures with 2E and vice versa, often on the fly, so I can see the appeal at the time of compatibility.

 

[an_idol_mind]

I was actually thinking about getting out 2nd edition again and converting the AC to an ascending scale as a houserule. It shouldn't be too complex, unless I'm missing something.

THAC0 converts to BAB as 20 - THAC0. So a THAC0 of 20 is +0 BAB; 19 is +1 etc.

AC would convert as 10 + (10 - 2nd edition AC).

So a 10 AC in 2nd edition would translate to a 10 in the houserule. 10 + (10 - 10). A 5 AC in 2nd edition would translate to a 15 in the houserule. 10 + (10 - 5). A -3 AC in 2nd edition would translate to a 23. 10 + (10 - -3).

This would be a relatively easy conversion guide that could have taken an Appendix in the 2nd edition PHB.

Retreater

That's what I used for a house rule in the last few years of 2nd edition. There was some initial resistance from people who liked THAC0, but after instituting it I never got any complaints.

 

[saskganesh]

Ascending AC is easier, but THAC0 is not difficult. At all. As for converting modules, splint mail is still splint mail and an x level fighter is still an x level fighter. The differences are quite minor. It's still a "quick roll to hit, quick roll for damage" system. Both play quickly.

 

[M.L. Martin]

To answer the original question: Castles & Crusades (ascending AC and saves linked to attributes were two things they wanted to do but either couldn't do for backwards compatibility or couldn't work out how to do) with a little less 1E/Gygaxian feel, a bit more polish, maybe not quite so unified a mechanic, and a few more mechanical bells & whistles (thief abilities divided into levels, for example).