Here are my thoughts, in no particular order. Keep in mind that I'm using the 3rd Edition of Chainmail, as that's the only PDF I've been able to find (and the only one that's available for sale right now). I would normally attempt to use the earliest iteration of something possible, but this was published back in the days when "edition" meant "an error-correcting and possible expansion of the work", instead of "a completely new thing with a similar name". I will also be frequently referring to Jason Vey's Supplement VI: Forbidden Lore, and the multi-authored, Aldarron-edited "Using Chainmail to Resolve OD&D Combats".
- According to Vey's interpretation of the Man to Man combat system, the pluses of a character's Fighting Capability score would refer to extra attacks, so a 1st-level Fighting Man would get 2 attacks per exchange of blows. This not only provides a boost to characters of all classes (although Magic-Users and Clerics obviously progress more slowly), but would make combat run much faster in general against humanoid opponents. It would be pretty easy to assume that, for instance, all orcs would be wearing leather armor and wielding clubs; I could just as easily change the entries for "No Armor", "Leather or Padded Armor", etc. to the corresponding AC values as detailed in Greyhawk.
- The Troop Type system seems pretty impractical unless actual mass combat is taking place, so I probably wouldn't be using it for a while yet.
- The fact that a combatant can't even attack on the Fantasy Combat Table (against dragons, giants, etc.) unless their Fighting Capability is equal to a Hero - or at least Hero -1 for some of the weaker opponents - is another good reason for me to consider starting characters off at 3rd or 4th level. This would at least allow fighters to use this system. Then again, I might as well just use the Alternative Combat System from D&D.
- Jousts seem pretty integral to D&D from the way they're described in The Underworld & Wilderness Adventures, and as I develop the wilderness of my planned game, I'm making sure to take jousting into account. (This leads to some interesting complications, given that one of the possibilities for the guards of a Superhero is a group of Heroes riding on rocs; one of my wilderness castle-dwellers is particularly fond of aerial jousts...)
- Hobbits are still present in the PDF that I have of Chainmail, as are ents and balrogs. I have no qualms about keeping these as their names in the campaign itself. If I had ten bucks for every time this conversation happened, I'd be rich:
Me: "You can play as a human, or a dwarf, elf, or halfling."
New Player: "What's a halfling?"
Me: "A hobbit."
- I need to get together with one of my friends and try out some of the Chainmail systems on their own, just to figure out how they work in play, so that I could better present them to my players.