It seems like the problem OP is having is that he doesn't understand why he is missing so much. So maybe they need to explain these mechanics better? Generally the HUD on the left side of the screen when hovering an attack over an enemy is quite descriptive, but maybe not everyone realizes that's there and has useful information.
As for offering an advantage for a streak of bad luck: some games use RNG mechanics where the actual chance is lowered each time it is successful, and the chance increases each time it fails, resulting in statistically same probability but reducing variance.
I don't personally want it, as it doesn't feel true to how a d20 works. But overall it isn't a bad RNG system.
They could also implement an easier difficulty mode where you get guarenteed successful rolls every now and then or something along those lines. Just throwing ideas here
And to make missing less annoying, I think speeding up AI turns would help a lot. Simultanous AI and animation speed setting. So you get to try again soon rather than wait 1 minute just to miss again.
