Snipers Mark lacks visual/auditory feedback on cast, especially with large bosses

Sometimes in the chaos of combat, it's hard to tell if your character actually casts Snipers Mark. The 'character pointing' animation is so small and the glow is so minuscule that it's easy to miss.

Additionally, with very large boss enemies, the top of their head is often positioned off-screen, so the player can't see if the mark has been applied. This is unfortunate in boss encounters, when the player needs to make split-second decisions on what to do next based on what state the boss is in.

A health bar debuff and/or a sound cue when the debuff is applied and/or a more prominent visual effect with bosses would help mitigate this.