- Would you consider using modifiers of -10/-20 or the like for man-to-man archery? Yes.
- Can we use the same modifiers indoors as outdoors (assuming that melee movement counteracts reduced range)? Yes.
- Should handheld missiles be without penalty? No.
- Should we totally forgo ranged modifiers in mass combat rules? Yes.
- Should creatures like giants get separate melee and ranged attack scores? No.
In general, I agreed with these opinions, and I was happy to build them into the way that Book of War works. For example: I suggested Question #5 as an option (giants should have crappier to-hits for missiles than melee), but that was decisively rejected, and it meant one less detail for me to include in BOW.
One other thing: At mass scale, Questions #1 (increase range penalties) and #4 (decrease range penalties) sort of cancel each other out. I actually tested Book of War with no ranged penalties at all, which is something that previously I argued for from a realism perspective, but it didn't make great gameplay in BOW. In particular, it made archers much too strong, or in other words, they had to be crazy-expensive to be balanced with other types (like: priced similar to cavalry), which itself is not terribly realistic. Therefore I decided to go with a middle ground like AD&D penalties of 0/-2/-5, which (divide by 3 and round to closest in this case), turns into 0/-1/-2 in the BOW d6 core mechanic. This made for some very nice play.
Other Archery Issues
To the right you'll see the Book of War missile-weapons table, including rate-of-fire (ROF), and maximum standard range in inches. Rate-of-fire is the number of dice one archer figure rolls in an attack -- when motionless; or, you can make a half-dice attack with up to a half-move. These are both similar to what you'll see for classic D&D (in particular for ROF, see text of Chainmail p. 11).
But here's an interesting observation about rate-of-fire: This does not imply or require that man-to-man rates of fire be the same. In fact, in my actual D&D games, I still run archery wherein bows get 1 shot per round, and crossbows 1/2. So why do they get effectively doubled at mass scale? Well, that's a function of the presumed internal formation of each 1:10 figure. Since the 10 men are usually arrayed in 2 ranks, a missile unit with everyone firing effectively gets twice as many attacks over the same time as a melee unit (with only a front of 5 men fighting at once). Or in other words: We've established that a single die-roll in BOW represents 15 attacks across 3 rounds of D&D (link). For a full figure of bowmen shooting over 3 rounds, that's 3×10=30 attacks, or 30/15 = 2 die-rolls in BOW. (Half that for crossbows.)
Conclusion: We might say that AD&D giving multiplied shots per turn for missiles (duplicating Chainmail) was actually in error, and the Basic D&D (Holmes/Moldvay/Mentzer) rule of just 1 shot per round for bows was, in this case, both more elegant and a more clear-headed model of what should be happening. (And as usual: Scaling issues are key.)
Another thing that I was compelled to consider: Mass archery at a distance is incapable of picking out individual opponents, and should have targets picked randomly (as per DMG p. 63, and plain common sense). So: Perhaps over the course of a round, so many arrows hit duplicate (already-killed) targets, that the overall effect is reduced to some degree? This prospect was investigated by simulation in the RPGBattle program. Fortunately, the "redundant shot" effect turns out to be significant in only one case -- if there are a great many archers, and very few potential targets, i.e., the victims are about to be all wiped out anyway. So it's an effect that is relievedly negligible for our purposes. See here for the spreadsheet analysis:
Something else that was quite popular in the earlier post comments (re: Question #5) was the idea of treating giants throwing stones as a kind of shattering/shrapnel area-of-effect weapon. Now, this was indeed what happened in Chainmail -- but it's ambiguous in OD&D, one of two options in Holmes, and then never again treated that way in any other edition of D&D (discussion here). So in light of this, and for balance and simplicity sake, I share the latter interpretation of Holmes -- giant stones are treated as a single-target weapon for 2d6 damage, and are treated by the system the same as any other missile-fire. (Rate-of-fire is 1/2 at man-to-man scale, and thus ROF 1 in BOW.)
Finally, one detail to keep in mind about the decision to use range modifiers that look like 0/-1/-2 in Book of War (analogous to AD&D mods): Note that the scale-switch from classic AD&D 1"=10 yards outdoors to BOW 1"=20' means that using the same range-in-inches (like 18" for a light crossbow) actually discounts the "real" distance for missile attacks by 2/3. As a result, the basic rule in BOW is that we really only deal with only two possibilities: under half range (no to-hit modifier) and over half range (at -1). For simplicity, in both gameplay effect and conversions using identical numbers, this was considered very desirable. The Optional Rules section contains the possible variant of extending out to long range (add another half-range, like a further 9" for crossbows), although at -2 to hit that makes for impossible shots in most cases anyway, so there's yet another reason to not worry about the missing extreme range.
And as a final final detail note this important item: Targets in heavy armor (plate, AH6 in BOW) are effectively immune to normal D&D missile attacks beyond short range (with -1 to hit, it's like AH7 versus d6). So keep that in mind for your tactical play.