What Evan has demonstrated with his list of rules is the modularity of the retro-clone. Here is a short list of all the rulesets he has cobbled together for his Nightwick Abbey campaign: LL, S&W, LotFP, AEC, AD&D and RC. We all have the the freedom to cobble together our own rules list from even more sources, if we so choose.
It gets better. Not only do we live in the age of the OGL but Dan Proctor has made his rule sets available as .txt files. Therefore, using the plethora publishing software available to us, we can edit these .txt files to reflect our own house rules.
It gets better. We can also save these house rules as a .pdf to distribute to our players. For those that are really ambitious (and have the cash), we can even to go the trouble of publishing these rules via a POD company and see them as a glorious hard cover.
It gets better. Even games that seem to be outliers like Epées & Sorcellerie have great ideas that can be swiped and written into house rules. For example, if anyone wants to convince a grumpy old grognard like myself to switch to AAC, all you have to do is cite E&S and how it gives players the freedom to use their Dex score for an AC if they don't like their armor's AC.
The real beauty, though, is that if I still want to have DAC in order to take advantage of Delta's Target 20 Algorithm (d20 + level + AC + mods ≥ 20), I can make a table converting Dex scores into DAC equivalents and edit that into my own house rules document:
Dex 18 = AC 1I reiterate: the more the merrier. Why? The more options we have, the more the game becomes ours — the more golden this golden age becomes.
Dex 17 = AC 2
Dex 16 = AC 3
Dex 15 = AC 4
Dex 14 = AC 5
Dex 13 = AC 6
Dex 12 = AC 7
Dex 11 = AC 8
Dex 10 or lower = AC 9