Guys, I'm gonna talk a little about other ASU suggestion for Rubick first.
I'm sure that it is obvious to you that most people want to improve the ultimate (Spell Steal) by making Rubick being able to steal more than 1 spell. IMO it's imbalance.
Spell Steal should literally steal spells
. Anyway, literally steal spell isn't my suggestion.
WARNING: My suggestion may be ridiculous but please think about it before making a comment :/
Improve Spell Steal casting range to global
casting range.. [Removed "decrease cooldown, no manacost and duration forever" Improvement due to current feedback]
My point is to make Casting Range Global.
Global Casting Range is NOT imbalance. Think about it.
Another Suggestion (newly added)
Reduce cooldown to 4s. No Manacost. (Global Casting Range not included).
Reason (Don't take this seriously)
Rubick is the son of Aghanim, therefore, Rubick's ultimate should be "ridiculously" strong while holding Aghanim's Scepter. He should really have ASU since Aghanim is his father...
At first, I thought AS will not be worth buying as casting range don't really matter, what Rubick wants is just to have a spell he steals.
Then, I realised that this can counter enemies with Global Casting range spell, you steal it from far, you use it too.
I believe there will be other circumstances where Global Casting Range will help.
IMPORTANT: I will accept negative comments, but please think through before making a comment. Please leave suggested changes that you think of one, I will consider it.