For the most part you're right. Your implied odds are not much of a factor on a suited board like this. Your odds are set by his holdings. The higher his heart, the better your implied odds. Ideally he would have the king of hearts in this situation. Imagine he did, and then imagine how your implied odds (opponent confidence) would be largely unaffected by any manipulation of betting pattern.

Your implied odds would however be increased if he had something like the J or 9 of hearts. Imagine you didn't raise the flop and he has the Qc 9h or Qc Jh. When the turn hits he'll bet out again and any show of strength by you will slam the action to a halt. On the contrary, if you raise the flop he puts more stock in the possibility that you may have a very strong hand that is NOT a flush. Not much more, but at least he's not isolating possibilities. He's calling down value bets, where he may fold if you wait to raise the turn.

The difference is so minute and varies from opponent to opponent. I wouldn't take implied odds into consideration on this type of board.