So I can see that PL got two new classes (ranger and paladin), and I suggest STS to add some to SL too. Of course, since SL is different from PL the classes would be different too.
Commencing brainstorm
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Sniper
The original idea is of course from...scorn snipers. But of course this class won't be able to one hit kill everything like the scorn snipers. However, as the name suggest, this class can do massive dmg in one hit, with much better hit rate. The unfortunate drawback would be low armor and slow atk speed.
Base stat: 5 str, 1 dex, 3 int.
Role: single target nuke.
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More ideas coming up. Post below if you have ideas too.