Landing your Q every 300 seconds is cool.
An anti-healing debuff to put on the enemy AD carry when ganking bot lane is better (fuck your heal).
A damage over time debuff to finish off enemies who flash away is better.
A slow/damage reduction to win your duels, prevent enemy escapes, and help yourself escape is better.
Q is already a ton of mobility. R already lets you initiate.
Ignite increases the chance your ganks/initiation will result in a kill or force enemy summoners.
Exhaust increases your own ability to duel, kite, and overall survive.
All while having a lower cooldown than flash (even with all the flash cooldown reduction tools).