Should Singed be changed so his Q isn't a toggle anymore?

Having Poison Trail as a toggle is fairly problematic. You can never catch Singed with his pants down (so to speak), and it forces his mana costs to be weird.

I know a lot of people will be skeptical about changing Singed's Poison Trail, but hear me out. Here's an example of how it could be changed.

Poison Trail For the next 8 seconds, Singed has increased health regeneration and leaves a poison cloud behind him; the cloud lasts for 3.25 seconds. Enemies standing in the cloud's trail are Poison icon poisoned for 2 seconds, taking magic damage every 0.25 seconds for the duration, continually refreshing while remaining in the affected area. 16/15/14/13/12 second cooldown. Costs X mana.

The reason for changing it like this is so you can't keep it going continuously until you get enough CDR, which allows opponents to capitalize on a cooldown while laning, or even post-laning if Singed doesn't focus on CDR.

But to compensate (and since Singed is already easily bullied), Singed gets some free health regeneration while Poison Trail is active, giving him some more sustain and letting him take a little more of a beating in lane. Additionally, Singed's other abilities could get their mana costs reduced thanks to this change; they normally have high costs to try and stymie Singed players who use quick toggles.

Of course, it doesn't have to be this way word-for-word, but changing it away from a toggle, I feel, is necessary to allow Singed to have more "balance levers" to pull.