If i play Armada and then a Poor House with 4 Treasure cards in hand, do i have $0?
I'll just state Donald had a reason to introduce the "-$1" token instead of having Bridge Troll say "At the start of his next turn, each other player gets -$1". It avoids exactly the issues people are talking about, and many more that might come up in the future or with translated versions of Dominion.
I know you make this card for yourself, and that's fine. You can make any card you like. Just don't expect people to be thrilled by something that breaks Dominion's design standards - especially if a cleaner implementation is allready available.
Having said that, i think nothing's generally wrong with the concept of a card that uses up your money for draw. Some suggestions:
Armada, $5
+3 Cards
Spend up to $2 you have. +1 Cards per $ spent.
Or:
Armada, $5
+3 Cards
Take your -$1 token. If you do: +2 Cards
Or:
Armada, $4
+5 Cards
When you do your first buy this turn, you may spend $3. If you don't, trash this.
Of course, they all are all a bit redundant to Storyteller, but that's of course because the general concept is the same.