DPR is a weak metric. Worrying about whether a build is within a +1/+1 weapon of another build is, quite frankly, pointless.
Which is better: +8 for 4d10 or 4 attacks at +8 for 1d10? The answer depends upon what you're fighting.
If you're facing multiple foes that have 5 hps each, the 4X +8 for 1d10 is much better. If your opponent has 22 hps, and it needs to die in 1 round.... +8 for 4d10 is much better (as it is all or nothing and you need all to get a good chance to get the kill). However both have the same DPR.
Every class, and every subclass, is playable. None of the are so overpowered as to prevent the game from being fun. If you're finding he game ruined by a build, I'll put it to you that the probem is best solved not by "fixing" the builds, but by taking a more productive approach to the game.