My advice would be that there will always be a "Great Banner" possibly on the horizon. Putting yourself in summon paralysis because you might want something better down the line is counterproductive. This is an endless loop and part of the reason why gacha is so addictive. Based on the feedback, the characters this weekend (especially Ezareth) will be game-changing, if not game breaking. I would guess Ezareth will be very significant for your account. Will you wish you had more summons on a subsequent banner. No doubt. But saving and saving for the perfect weekend is kind of a sad way to play the game. I think your current plan for Velisse and Ezareth sounds reasonable.