Suzune is a 1-dimensional character with one goal, wipe out the enemy before she gets wiped out. She has high attack, low HP and low defense.
Suzune is an Attack type Accele gorrila with an AOE Magia, meaning if she lives long enough she can sweep through a challenge quest with magia. In a single triple Accele combo without another other bonuses, she can gain 60MP and eventually get magia by turn 3.
An alternative strategy is to rely on her personal memo Lucky Charm gives her the ability to make all her disks crit allowing her to sweep through a 1-wave boss in the first turn. This is exceptional useful against the story boss fights in Chapter 9 episode 34 and 46, as well as Chapter 10 episode 3 battle 1, episode 4 battle 2. This strategy works best with a team of 2 and the Garnish Everything Cutely! memoria to redraw discs and ensure her discs are drawn. This strategy pairs exceptionally well with The Sword Which Strikes in the Space Between Light and Dark, a limited memo on Suzune's banner Cross Connection Pickup Gacha as she can crit with an extra 45% attack up guaranteed. This can be further optimized by using Kyubey Knight Breaking Through and getting ACB combo.
With Suzune's connect, she give her allies more damage output and that's that.
Suzune lacks defensive options, luckily she can mitigate that with allies such as Kaname Madoka or Misono Karin. The two of which have significantly more bulk and help accel teams gain magia quickly. In addition, the two of them can work in a Light Flame Tercio formation team well. Free to play alternatives that can maintain the advantageous formation include Tamaki Iroha and Tsuruno Yui, though they are not as bulky and do not support a quick magia gain. They do provide increased damage output with their connects.
Connect is useful for cleaning up
Easy AOE Magia
Low Defense and HP
Suzune functions effectively the same from PVE to PVP. However she loses out in her ability to use her one turn extreme burst damage. That being said, she can substitute with a turn two magia to close off weaker teams or large teams that can finish her off in one turn. This relies on Suzune having memos such as Because the World Is Full of Wishes or Keep This a Secret From Everyone! MLB. This lets her gain 86.1525 of her accel combo. From taking damage, she gains 14.4 thus getting her 100MP in one turn. Note that Iroha of the Midsummer Beach just falls short of giving Suzune 100 MP giving her a mere 99.5375. The other memo to equip are those that defense to assist her in surviving the first turn and again The Sword Which Strikes in the Space Between Light and Dark allowing her to consistently deal more damage in the first turn to pick off water types that may pose a risk to her. I Made Friends! is a decent alternative though if the crit does not activate, it dishes out less damage.
With the former strategy Suzune's magia comes into play for picking off the survivors of her magia as it has a chance to Burn the enemy preventing them from dodging her follow up attacks from her two remaining disks. In addition, Suzune has increased chance to crit ensuring the kill further.
Suzune's low defense can be used strategically in her favor with allies such as Misono Karin who has defenses in the same ball park of 7000ish. This allows Karin to be a target as Suzune can cleave through enemies while again building up that magia. Tsuruno Yui is another good ally to be a meat shield before Suzune gets hit.