Metalgarurumon is the best answer for security control with the trashing of security if the opponent has no play cost of 6 or less, it covers the match-up so well.. and Metalgarurumon also helps a little bit out against the rookie rush match up.
Ultimate Flare is your answer for rookie rush. If you have it in hand or in security, you would win the matchup, so it's a coin toss if you are getting that card or not. A big play against rookie rush is just giving them all the memory and put them on their turn to 10, if they use all of the cards they have in hand and potentially hit an Ultimate Flare in security or get hit from playing from the hand next turn, it makes the rookie rush match up to run out of gas so fast.