Sivir's spell shield is "awkward"

Hello interesting people, my name is ScarletStump and I enjoy playing League. I am not well-informed enough to blindly consider trusting my opinion.

Playing Sivir is fun. She's unique and has a lot of choices to make that impact the game. However, there is one aspect of her kit that can create an unsavory experience for either the Sivir player or the opponent them self: Spell Shield. The ability concept is simple and fairly straight forward, but the problems that come with using it stem from a lack of clarity and inconsistent coding across the board which result in a lot of guess work or extensive knowledge to take full advantage of the power that such a simple skill provides. This culminates to create an awkward spell/interacrion, something that generally lowers the enjoyment.

I can go into detail if people think it's important enough.

TL;DR: Either Sivir's spell shield could use some clarity work, abilities in general could use some consistency work, or both.

What are your thoughts? What aspect do I seem to be ignoring? Did I mention anything that you haven't considered before (even if you remain unconvinced)? I'm truly interested in what others have to say.

Keep smiling. Anything else is only hurting yourself.