I’m not knocking long cues, but longer arrows do not fly more or less straight than shorter ones. Good arrow flight is achieved through careful tuning of numerous interrelated variables, including length along with stiffness, the weight of the tip, balance point, draw weight (how hard it is to pull the string back), the type of bow, etc. Regardless, I don’t think the physics of arrow flight (or javelins) are relevant to cues unless you plan to shoot (or throw) your cue through the air.
I just remembered that I have a crossbow, which as we all know has a substantially shorter arrow than that of a standard compound or long bow. You're right about that, both of them fly fast and straight. I was never any good with either one but it did seem like I had better luck with a regular bow. Arrows can absolutely be related to cues in every aspect you mentioned. Length, stiffness (taper), weight of the tip (LD shafts), balance point...those are all key aspects of a cue. I suppose you could even say how hard it is to pull the cue back and take the total weight into consideration like you would the draw weight of a bow. I know a few people that thank goodness they never had a broad head on the end of their cue because they were almost olympic material when it came to throwing them :duck: