Armadyl Crossbow is an okay weapon, but that's where it stops at.
The only real use for it is in raids. Everywhere else Toxic Blowpipe out dps' it.
I would like to see this changed, as it's a fun weapon to use, and if it was slightly buffed it would give reason to actually use it (outside of raids) and give you a reason to farm for items such as Odium Ward, Twisted Buckler, and even items such as Elysian Spirit Shield.
My Suggestion:
Buff it just a little bit.
I'm not suggesting for it to be op, but at least buff it a little but, make it more in-line with Blowpipe, and give people a reason to use it outside of raids.