Waiting until the signing period in D1 means you will most likely end up with crappy recruits. I'm not as experienced at D1 recruiting as many others on the board but I've had 10 seasons of D1 recruiting (been to the tourney 7 times, with 1 Final 4 and another Elite 8) and I've always recruited from cycle one. The reason is D1 is the most populated division and you get much more money to recruit with so there are more coaches who can afford to pump in a ton of money into recruits which means there are less good recruits left over. Also there is a smaller pool of recruits, high level D2 and D3 schools not only have the best players that are listed at their division to choose from but also can pull down or have higher level recruits drop to them. That doesn't happen in D1, there's no higher pool to reach too. I've never pulled anybody down at D1, I don't even know if you have to but if you do you probably want to leave that recruit alone because a school with a much better prestige will probably end up going after that recruit.
So basically don't wait, don't try to pulldown just go after the best guys you think you can get.