Can whe buff Tahm active ult?

Tahm ult has a pretty hugh channel time even if you reactivate it directly. Not to mention it has a 100 mana cost. For rank II & rank III this is fine. But honnestly I find his rank I active a little bit difficult to use. Combines with the channel time this 4000 range feels short for flanking. Their are so many situations when using it doesn't really provide an advantage for your team. I feel the rank 1 is the biggest issue. Ones 11 I feel it becomes usefull.

Since it provides pure utility I was wondering what you guys think if whe remove the mana cost? Ones you get level 11 and higher mana cost isn't really an issue anymore so no cost wouldn't really be a hugh buff since you have the channeling duration if you want to use it defensively.

Alternatively what about buffing the range a tiny bit on earlyer ranks like 4500 / 5250 / 6000.