(( Syn Ace,
If you think that's bad-ass, I've seen someone else do that... and then put a ball-and-socket joint on the weapon, so it litterally has a 1/2-sphere LOS. Not only can it peak over people and things, it can also peek around them too! Super-ultra-mondo-delux-engineering genius at its best, I say.
Yeah, True-Line-of-Sight was not thought out terribly well at all.
All,
For guess ranges, if you had a basic understanding of geometry, you could guess pretty well. You're already practically given to legs of a triangle. Not to mention that you only really started 20" - 24" away, which basically gives you your starting guess right there. From that point forward, start guessing at {24" - (enemy march movement rate x (turn number-1))}. ))