Deviations from basic strategy due to the count in blackjack?
The short answer to your question is YES.  This is the whole reason for counting, to understand how to change your bets and strategy to account for the count and to take advantage of the change in the odds.

This is also how casino's know that you're counting.  Once they are deep into the deck, you start betting higher, which is a signal to them that you're counting, in which case, they'll escort you out the door.