Since this monster negates all spell cards, it is suggested that you use it in a deck with little to no spell cards except Level Up.
The Horus the Black Flame Dragon line of monsters are quite similar to this card as they are both able to negate spells. The final version of Horus could be considered better since it allows you to activate your own spells and has more attack, while Silent Sworsman negates all. Although one advantage of using Silent Swordsman is that it negates spell cards that are already on the field, which Horus cannot negate.
The condition for upgrading Silent Swordsman LV5 to LV7 is quite situational as your opponent will rarely ever allow you to attack directly. To make it easier to attack directly, you can use Shooting Star Bow - Ceal or just use Level Up to instantly upgrade him.
Combine Silent Swordsman LV7 to other cards that can lockdown your opponent's monster effects and trap effects for a complete lockdown. Destiny Hero Plasma can be used to deal with monster effects, you can use Pitch-Black Warwolf or Mirage Dragon for trap cards during the battle phase.
Floodgate works on literally everything. Including God Cards. Because it activates one step after the special summon/summon itself. Whether it's inherent special summon or not, the Floodgates will activate. Reason why it works on every other LEVEL UP arch type card as well.
iirc, Jinzo and Silent Swordsman effect are Continuous effects and Angel 07 only negates Trigger, Ignition, and Quick Effect which needs an activation, hence her effect: "...the effects of Effect Monsters cannot be ACTIVATED." so this trio combo should work, but yeah... it will be a somewhat difficult.