Sion's Passive Change

I play Sion a lot and he is one of the coolest champions to play, but recently I've been feeling like Sion's passive needs to be changed a little bit. Sion's passive doesn't allow him to activate summoner spells like smite or flash, I know that this may be an op thing on Sion but I feel it defeats the purpose of his passive if someone uses flash and he is unable to catch them what so ever. So if possible if you could allow him to activate summoner spells or item effects. Just a little thing I thought I'd throw out there.