Before I went archer (long, long time ago), I was a crossbowman. And I can tell you that arbalest are (or at least were, when people weren't at level 35) extremely deadly on siege, or on large maps with covers (doesn't matter if it's a tree, a ruin, or a shielder), since you could easily kill someone with 1 or two bolts, from far. Now, the average player got 60+ body armor, and landing a headshot is the only way to kill someone quickly. The big downside is the speed of the reload : an heavy crossbow is much more suited for fighting in medium ranges than arbalest (basically, if you're a battle player, you won't find yourself with an arbalest, or it's at your own risks), since if you miss, the guy won't let you the time to relaoad, while it's not always the case with the heavy crossbow. The ranged buff will probably have its effects on crossbows, and I won't be able to charge a guy bearing an arbalest, which is logical after all.