I really like the warning concept on the ult.
Not only does the Alchemist support the team, the team has to defend the Alchemist for however long the charge-up is.
This also allows for a distraction, say a sneaky bomb plant while everyone is hunting for the alchemist. Or suppose a lion came in while the team started hunting down the Alchemist and caused absolute total chaos among the enemy team.
Forward, the Light Brigade!'
Was there a man dismay'd?
Not tho' the soldiers knew
Some one had blunder'd:
Theirs not to make reply,
Theirs not to reason why,
Theirs but to do and die:
Into the valley of Death
Rode the six hundred. ~Alfred, Lord Tennyson